XYY syndrome , also known as Jacobs syndrome , is an aneuploid genetic condition in which a male has an extra Y chromosome . There are usually few symptoms. These may include being taller than average and an increased risk of learning disabilities . The person is generally otherwise normal, including typical rates of fertility .
112-492: The condition is generally not inherited but rather occurs as a result of a random event during sperm development . Diagnosis is by a chromosomal analysis , but most of those affected are not diagnosed within their lifetime. There are 47 chromosomes, instead of the usual 46, giving a 47,XYY karyotype . Treatment may include speech therapy or extra help with schoolwork, however outcomes are generally positive. The condition occurs in about 1 in 1,000 male births. Many people with
224-665: A Maryland institution were chemically sterilized to attempt to maintain "normal behavior," despite this the paper found no major behavioral differences between XY and XYY individuals. In August 1976, Science published a retrospective cohort study by Educational Testing Service psychologist Herman Witkin and colleagues that screened the tallest 16% of men (over 184 cm (6'0") in height) born in Copenhagen from 1944 to 1947 for XXY and XYY karyotypes, and found an increased rate of minor criminal convictions for property crimes among sixteen XXY and twelve XYY men may be related to
336-460: A molecule that encodes genetic information. DNA is a long polymer that incorporates four types of bases , which are interchangeable. The Nucleic acid sequence (the sequence of bases along a particular DNA molecule) specifies the genetic information: this is comparable to a sequence of letters spelling out a passage of text. Before a cell divides through mitosis , the DNA is copied, so that each of
448-493: A 2020 study. DNA damages present in spermatozoa in the period after meiosis but before fertilization may be repaired in the fertilized egg, but if not repaired, can have serious deleterious effects on fertility and the developing embryo. Human spermatozoa are particularly vulnerable to free radical attack and the generation of oxidative DNA damage. (see e.g. 8-Oxo-2'-deoxyguanosine ) Exposure of males to certain lifestyle, environmental or occupational hazards may increase
560-540: A 34-year-old XYY serial killer . The false stereotype of XYY boys and men as violent criminals has also been used as a plot device in the horror films Il gatto a nove code in February 1971 (dubbed into English as The Cat o' Nine Tails in May 1971) and Alien 3 in May 1992. The main character of the 2005 film Neo Ned is a neo-nazi who has an extra Y chromosome. Why do men commit crimes of violence? For some,
672-662: A 47,XYY karyotype, and mischaracterized them as aggressive and violent criminals. Over the next decade, almost all published XYY studies were on height-selected, institutionalized XYY males. In January 1968 and March 1968, The Lancet and Science published the first U.S. reports of tall, institutionalized XYY males by Mary Telfer, a biochemist , and colleagues at the Elwyn Institute . Telfer found five tall, developmentally disabled XYY boys and men in hospitals and penal institutions in Pennsylvania , and since four of
784-458: A DNA sequence within a chromosome is known as a locus . If the DNA sequence at a particular locus varies between individuals, the different forms of this sequence are called alleles . DNA sequences can change through mutations , producing new alleles. If a mutation occurs within a gene, the new allele may affect the trait that the gene controls, altering the phenotype of the organism. However, while this simple correspondence between an allele and
896-648: A decade before the first reported sex chromosome aneuploidy. An analogous technique to screen for Y-chromosome aneuploidies by noting supernumerary "male" sex chromatin bodies was not developed until 1970, a decade after the first reported male sex chromosome aneuploidy. The first published report of a man with a 47,XYY karyotype was by the American cytogeneticist Avery Sandberg and his colleagues at Roswell Park Comprehensive Cancer Center (then known as Roswell Park Memorial Institute) in Buffalo, New York in 1961. It
1008-691: A false stereotype) to the subjects, and that the unblinded experimental design could not produce meaningful results regarding the subjects' behavior. In December 1974, the Harvard Standing Committee on Medical Research issued a report supporting the Boston XYY study, and in March 1975, the faculty voted 199–35 to allow continuation of the study. After April 1975, screening of newborns was discontinued—changes to informed consent procedures and pressure from additional advocacy groups, including
1120-612: A few generations and then would remove variation from a population on which natural selection could act. This led to Darwin adopting some Lamarckian ideas in later editions of On the Origin of Species and his later biological works. Darwin's primary approach to heredity was to outline how it appeared to work (noticing that traits that were not expressed explicitly in the parent at the time of reproduction could be inherited, that certain traits could be sex-linked , etc.) rather than suggesting mechanisms. Darwin's initial model of heredity
1232-517: A letter of last July 3, indicating that 100 of 101 cells in a sample of Speck's blood studied after the original tests showed the normal 46 chromosomes. The other cell had 45, regarded by the Vanderbilt investigators as having no significance. Heredity Heredity , also called inheritance or biological inheritance , is the passing on of traits from parents to their offspring; either through asexual reproduction or sexual reproduction ,
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#17327808264061344-509: A long history of arrests, frequently beginning at an early age. On reading newspaper accounts of Richard Speck, who murdered eight Chicago student nurses in 1966, we noted all these traits and therefore concluded that Speck was a likely candidate for the XYY disorder. Independently, a cytogenetic laboratory in Chicago confirmed this hunch, reinforcing our inclination to believe that the XYY syndrome
1456-461: A main source—introduced the XYY genetic condition to the general public in a three-part series on consecutive days that began with a Sunday front-page story about the planned use of the condition as a mitigating factor in two murder trials in Paris and Melbourne —and falsely reported that Richard Speck was an XYY male and that the condition would be used in an appeal of his murder conviction. The series
1568-407: A mean of 120. For the eleven of fourteen boys with siblings, in nine instances their siblings were stronger academically, but in one case the subject was performing equal to, and in another case superior to, his siblings. Some medical geneticists question whether the term " syndrome " is appropriate for this condition because many people with this karyotype appear normal. In June 1970, The XYY Man
1680-460: A mode of inheritance is also achieved primarily through statistical analysis of pedigree data. In case the involved loci are known, methods of molecular genetics can also be employed. An allele is said to be dominant if it is always expressed in the appearance of an organism (phenotype) provided that at least one copy of it is present. For example, in peas the allele for green pods, G , is dominant to that for yellow pods, g . Thus pea plants with
1792-691: A newborn screening program received remedial reading teaching compared to 18% (4 of 22) in an above-average-IQ control group of 46,XY boys matched by their father's social class. In Boston , USA 55% of 47,XYY boys (6 of 11) identified in a newborn screening program had learning difficulties and received part-time resource room help compared to 11% (1 of 9) in an above-average-IQ control group of 46,XY boys with familial balanced autosomal chromosome translocations . Developmental delays and behavioral problems are also found, but these characteristics vary widely among affected boys and men, are not unique to 47,XYY and are managed no differently from in 46,XY males. Aggression
1904-411: A part of early Lamarckian ideas on evolution. During the 18th century, Dutch microscopist Antonie van Leeuwenhoek (1632–1723) discovered "animalcules" in the sperm of humans and other animals. Some scientists speculated they saw a "little man" ( homunculus ) inside each sperm . These scientists formed a school of thought known as the "spermists". They contended the only contributions of the female to
2016-412: A result of oligospermia or sperm chromosomal abnormalities. According to certain psychological studies, people with XYY syndrome may have problems with impulse control and emotional regulation. Increased testosterone levels were found to be correlated with an increased risk of aggressive behavior in incarcerated males with 47,XYY syndrome. 47,XYY is not inherited; it usually occurs as a random event during
2128-426: A signal that the cell should not be rejected. The female immune system might otherwise attack sperm in the reproductive tract . The specific glycoproteins coating sperm cells are also utilized by some cancerous and bacterial cells, some parasitic worms, and HIV-infected white blood cells, thereby avoiding an immune response from the host organism . The blood-testis barrier , maintained by the tight junctions between
2240-413: A tail known as a flagellum 50 μm long. The flagellum propels the sperm cell (at about 1–3 mm/minute in humans) by whipping in an elliptical cone. Sperm have an olfactory guidance mechanism , and after reaching the fallopian tubes , must undergo a period of capacitation before penetration of the ovum. Head: It has a compact nucleus with only chromatic substance and is surrounded by only
2352-468: A thin rim of cytoplasm. Above the nucleus lies a cap-like structure called the acrosome , formed by modification of the Golgi body, which secretes the enzyme spermlysin ( hyaluronidase, corona-penetrating enzyme, zona lysin, or acrosin ), that is necessary for fertilization. As the spermatozoon approaches the egg, it undergoes the acrosome reaction in which the membrane surrounding the acrosome fuses with
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#17327808264062464-489: A trait works in some cases, most traits are more complex and are controlled by multiple interacting genes within and among organisms. Developmental biologists suggest that complex interactions in genetic networks and communication among cells can lead to heritable variations that may underlie some of the mechanics in developmental plasticity and canalization . Recent findings have confirmed important examples of heritable changes that cannot be explained by direct agency of
2576-600: A two-day XYY conference in Chevy Chase, Maryland . In December 1969, with a grant from the NIMH Center for Studies of Crime and Delinquency, cytogeneticist Digamber Borgaonkar at Johns Hopkins Hospital began a chromosome survey of (predominantly African-American) boys ages 8 to 18 in all Maryland institutions for delinquent, neglected, or mentally ill juveniles, which was suspended from February–May 1970 due to an American Civil Liberties Union (ACLU) lawsuit regarding
2688-403: A variety of ideas about heredity: Theophrastus proposed that male flowers caused female flowers to ripen; Hippocrates speculated that "seeds" were produced by various body parts and transmitted to offspring at the time of conception; and Aristotle thought that male and female fluids mixed at conception. Aeschylus , in 458 BC, proposed the male as the parent, with the female as a "nurse for
2800-505: A very few early case reports, but dermatologists specializing in acne now doubt the existence of a relationship with 47,XYY. Prenatal testosterone levels are normal in 47,XYY males. Most 47,XYY males have normal sexual development and have normal fertility. In contrast to the other common sex chromosome aneuploidies — 47,XXX and 47,XXY ( Klinefelter syndrome )—the average of the IQ scores of 47,XYY boys identified by newborn screening programs
2912-445: Is 21 years. The capacitation is the final phase of spermatozoa development, when they acquire the capability to fertilize the oocyte. In vivo, it happens during ejaculation, when spermatozoa leave the vagina and come in the superior female reproductive tract. In vitro, it happens when the spermatozoa is washed and purified. Almost 30-40% of infertility is due to male factor, so several strategies have been created in order to recover
3024-404: Is a moving form of the haploid cell that is the male gamete that joins with an ovum to form a zygote . (A zygote is a single cell, with a complete set of chromosomes , that normally develops into an embryo .) Sperm cells contribute approximately half of the nuclear genetic information to the diploid offspring (excluding, in most cases, mitochondrial DNA ). In mammals, the sex of
3136-433: Is a necessary medium for sperm and egg to meet. Algae and lower plant sperm cells are often multi-flagellated (see image) and thus morphologically different from animal spermatozoa. Some algae and fungi produce non-motile sperm cells, called spermatia. In higher plants and some algae and fungi, fertilization involves the migration of the sperm nucleus through a fertilization tube (e.g. pollen tube in higher plants) to reach
3248-428: Is called the powerhouse of the sperm. It also has a ring centriole (annulus) that form a diffusion barrier between the middle piece and the principal piece and serve as a stabilizing structure for tail rigidity. Tail: The flagellum is the longest part (50 μm), having an axial filament surrounded by cytoplasm and plasma membrane, but at the posterior end the axial filament is naked. The flagellum gives movement to
3360-404: Is growing evidence that there is transgenerational inheritance of epigenetic changes in humans and other animals. The description of a mode of biological inheritance consists of three main categories: These three categories are part of every exact description of a mode of inheritance in the above order. In addition, more specifications may be added as follows: Determination and description of
3472-400: Is not seen more frequently in 47,XYY males. Patients with Jacobs syndrome have been shown to have a higher risk of developing certain diseases such as asthma , seizure problems, and tremors. Some 47,XYY patients have been found to have genitourinary malformations. These include cryptorchidism, hypoplastic scrotum, microphallus, and hypospadias. These men could be diagnosed with infertility as
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3584-411: Is not usually diagnosed until learning issues are present. The syndrome is diagnosed in an increasing number of children prenatally by amniocentesis and chorionic villus sampling in order to obtain a chromosome karyotype, where the abnormality can be observed. It is estimated that only 15–20% of children with 47,XYY syndrome are ever diagnosed. Of these, approximately 30% are diagnosed prenatally. For
3696-570: Is really coming of age. It seems quite possible that in the XYY male, exemplified by Speck, biologists are describing in genetic terms a certain type of defective criminal who has long been explicitly recognized by the forensic psychiatrist. Dr. Pergament said he and Dr. Sato, a research fellow, had absolutely no connection with the Speck case and never examined Speck. The report was also denied by Speck's attorney, Public Defender Gerald W. Getty. "I never knew those doctors existed before I read about them in
3808-410: Is referred to a total amount of >39 mill ejaculated , >32% with progressive motility and >4% normal morphology. Also, a normal ejaculation in humans must have a volume over 1.5 ml, being an excessive volume 6 ml per ejaculation ( hyperspermia ). An insufficient volume is called hypospermia . These problems are related to several complications in spermatozoa production, for example: Approaching
3920-399: Is responsible for the influx of calcium. The sudden rise in calcium levels causes the flagellum to form deeper bends, propelling the sperm more forcefully through the viscous environment. Sperm hyperactivity is necessary for breaking through two physical barriers that protect the egg from fertilization. The second process in sperm activation is the acrosome reaction . This involves releasing
4032-410: Is that developmental biology (' evo-devo ') played little part in the synthesis, but an account of Gavin de Beer 's work by Stephen Jay Gould suggests he may be an exception. Almost all aspects of the synthesis have been challenged at times, with varying degrees of success. There is no doubt, however, that the synthesis was a great landmark in evolutionary biology. It cleared up many confusions, and
4144-604: The Children's Defense Fund , having led to the discontinuation of the last active U.S. newborn screening programs for sex chromosome abnormalities in Boston and Denver. In a paper published in New Scientist on November 14, 1974 entitled "XYY syndrome: a dangerous myth" found no link was found between having an extra Y chromosome and violent behavior. According to the paper, adolescents found to have an extra Y chromosome in
4256-487: The Illini Variable Temperature (IVT) diluent, which have been reported to be able to preserve high fertility of spermatozoa for over seven days. The IVT diluent is composed of several salts, sugars and antibacterial agents and gassed with CO 2 . Semen cryopreservation can be used for far longer storage durations. For human spermatozoa, the longest reported successful storage with this method
4368-786: The Karolinska Institute in Stockholm first reported intense fluorescence of the A T -rich distal half of the long arm of the Y chromosome in the nuclei of metaphase cells treated with quinacrine mustard. In April 1970, Peter Pearson and Martin Bobrow at the MRC Population Genetics Unit in Oxford and Canino Vosa at the University of Oxford reported fluorescent "male" sex chromatin bodies in
4480-514: The Moravian monk Gregor Mendel who published his work on pea plants in 1865. However, his work was not widely known and was rediscovered in 1901. It was initially assumed that Mendelian inheritance only accounted for large (qualitative) differences, such as those seen by Mendel in his pea plants – and the idea of additive effect of (quantitative) genes was not realised until R.A. Fisher 's (1918) paper, " The Correlation Between Relatives on
4592-547: The Sertoli cells of the seminiferous tubules, prevents communication between the forming spermatozoa in the testis and the blood vessels (and immune cells circulating within them) within the interstitial space . This prevents them from eliciting an immune response. The blood-testis barrier is also important in preventing toxic substances from disrupting spermatogenesis. Fertilization relies on spermatozoa for most sexually reproductive animals. Some species of fruit fly produce
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4704-679: The prostate gland dissolves the clot, allowing the sperm to progress optimally. The spermatozoon is characterized by a minimum of cytoplasm and the most densely packed DNA known in eukaryotes . Compared to mitotic chromosomes in somatic cells , sperm DNA is at least sixfold more highly condensed. The specimen contributes with DNA / chromatin , a centriole , and perhaps also an oocyte -activating factor (OAF). It may also contribute with paternal messenger RNA (mRNA), also contributing to embryonic development. The human spermatozoon contains at least 7500 different proteins . Human sperm genetics has been associated with human evolution , per
4816-420: The "supermale." He is also unusually tall and somewhat retarded, but appears to be highly, perhaps too highly, sexually motivated... We were intrigued by Dr. Jacobs' contention that an extra Y chromosome results in tall stature, mild mental retardation, and severely disordered personality characterized by violent, aggressive behavior. We therefore planned to confirm and extend her studies. Syndrome Status for
4928-851: The British cytogeneticist Patricia Jacobs did indeed contribute meaningfully to our knowledge of XYY. In December 1965 and March 1966, Nature and The Lancet published the first preliminary reports by Jacobs and her colleagues at the MRC Human Genetics Unit at Western General Hospital in Edinburgh of a chromosome survey of 315 male patients at State Hospital in Carstairs , Lanarkshire — Scotland 's only special security hospital for developmentally disabled people —that found nine patients, ages 17 to 36, averaging almost 6 ft. in height (avg. 5'11", range: 5'7" to 6'2"), had
5040-453: The British science fiction TV series Doomwatch featured an XYY boy expelled from school because his genetic condition led him to be falsely accused of nearly blinding another boy. A November 1993 episode of the American police procedural TV series Law & Order , "Born Bad", portrays a 14-year-old XYY sociopathic murderer. The May 2007 season finale episode, "Born To Kill", of the American police procedural TV series CSI: Miami depicts
5152-492: The DNA molecule. These phenomena are classed as epigenetic inheritance systems that are causally or independently evolving over genes. Research into modes and mechanisms of epigenetic inheritance is still in its scientific infancy, but this area of research has attracted much recent activity as it broadens the scope of heritability and evolutionary biology in general. DNA methylation marking chromatin , self-sustaining metabolic loops , gene silencing by RNA interference , and
5264-602: The IQ scores of 47,XYY boys were usually slightly lower than those of their siblings. In Edinburgh, fifteen 47,XYY boys with siblings identified in a newborn screening program had an average 104.0 verbal IQ and 106.7 performance IQ, while their siblings had an average 112.9 verbal IQ and 114.6 performance IQ. Approximately half of 47,XYY boys identified by newborn screening programs had learning difficulties—a higher proportion than found among siblings and above-average-IQ control groups. In Edinburgh, 54% of 47,XYY boys (7 of 13) identified in
5376-501: The Supposition of Mendelian Inheritance " Mendel's overall contribution gave scientists a useful overview that traits were inheritable. His pea plant demonstration became the foundation of the study of Mendelian Traits. These traits can be traced on a single locus. In the 1930s, work by Fisher and others resulted in a combination of Mendelian and biometric schools into the modern evolutionary synthesis . The modern synthesis bridged
5488-539: The XYY The XXY male has long been thought to display a constellation of symptoms that makes him diagnosable; that is, he has achieved syndrome status. It would seem that the XYY male is fast achieving similar status. His symptoms, as we and other laboratories tend to think of them, are: extremely tall stature, long limbs and strikingly long arm span, facial acne, mild mental retardation, severe mental illness (including psychosis) and aggressive, antisocial behavior with
5600-437: The alleles in an organism. Spermatozoon A spermatozoon ( / s p ər ˌ m æ t ə ˈ z oʊ . ən , ˌ s p ɜːr m ə t ə -/ ; also spelled spermatozoön ; pl. : spermatozoa ; from Ancient Greek σπέρμα ( spérma ) 'seed' and ζῷον ( zôion ) 'animal') is a motile sperm cell produced by male animals relying on internal fertilization. A spermatozoon
5712-614: The annual meeting of the American Psychiatric Association , Telfer and her Elwyn Institute colleagues reported that case studies of the institutionalized XYY and XXY males they had found convinced them that XYY males had been falsely stigmatized and that their behavior may not be significantly different from chromosomally normal 46,XY males. In June 1969, the National Institute of Mental Health (NIMH) Center for Studies of Crime and Delinquency held
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#17327808264065824-405: The cell. Semen has an alkaline nature and the spermatozoa do not reach full motility (hypermotility) until they reach the vagina , where the alkaline pH is neutralized by acidic vaginal fluids. This gradual process takes 20–30 minutes. During this period, fibrinogen from the seminal vesicles forms a clot, securing and protecting the sperm. Just as they become hypermotile, fibrinolysin from
5936-401: The complete set of genes within an organism's genome is called its genotype . The complete set of observable traits of the structure and behavior of an organism is called its phenotype . These traits arise from the interaction of the organism's genotype with the environment . As a result, many aspects of an organism's phenotype are not inherited. For example, suntanned skin derives from
6048-503: The condition are unaware that they have it. The condition was first described in 1961. People with the 47,XYY karyotype have an increased growth rate from early childhood, with an average final height approximately 7 centimetres ( 2 + 3 ⁄ 4 in) above expected final height. In Edinburgh , Scotland , eight 47,XYY boys born 1967–1972 and identified in a newborn screening programme had an average height of 188.1 cm (6 ft 2 in) at age 18—their fathers' average height
6160-405: The contents of the acrosome, which disperse, and the exposure of enzymes attached to the inner acrosomal membrane of the sperm. This occurs after the sperm first meets the egg. This lock-and-key type mechanism is species-specific and prevents the sperm and egg of different species from fusing. There is some evidence that this binding is what triggers the acrosome to release the enzymes that allow
6272-510: The development of individuals with sex chromosome abnormalities. In May 1997, Nature Genetics published the discovery by Ercole Rao and colleagues of the X/Y chromosome pseudoautosomal region (PAR1) SHOX gene, haploinsufficiency of which leads to short stature in Turner syndrome (45,X). It was subsequently postulated that the increased gene dosage of three SHOX genes leads to tall stature in
6384-504: The development of over 300 children and young adults with sex chromosome abnormalities identified in the screening of almost 200,000 consecutive births in hospitals in Denver, Edinburgh, New Haven, Toronto, Aarhus, Winnipeg, and Boston from 1964 to 1975. These seven studies—the only unbiased studies of unselected individuals with sex chromosome abnormalities—have replaced the older, biased studies of institutionalized individuals in understanding
6496-417: The discoveries of 47,XXY , 45,X and 47,XXX in 1959. Even the much less common 48,XXYY had been discovered in 1960, a year before 47,XYY. Screening for those X chromosome aneuploidies was possible before the advent of human chromosome analysis by noting the presence or absence of "female" sex chromatin bodies ( Barr bodies ) in the nuclei of interphase cells in buccal smears , a technique developed
6608-507: The discovery by cytogeneticists Joe Hin Tjio and Albert Levan at Lund University in Sweden that the normal number of chromosomes in diploid human cells was 46—not 48, as had been believed for the preceding thirty years. In the wake of the establishment of the normal number of human chromosomes, 47,XYY was the last of the common sex chromosome aneuploidies to be discovered, two years after
6720-419: The egg cell is a rather complex, multistep process of chemotaxis guided by different chemical substances/stimuli on individual levels of phylogeny. One of the most significant, common signaling characters of the event is that a prototype of professional chemotaxis receptors, formyl peptide receptor (60,000 receptor/cell) as well as the activator ability of its ligand formyl Met-Leu-Phe have been demonstrated in
6832-430: The egg cell. Spermatozoa are produced in the seminiferous tubules of the testicles in a process called spermatogenesis . Round cells called spermatogonia divide and differentiate eventually to become spermatozoa. During copulation , the cloaca or vagina gets inseminated , and then the spermatozoa move through chemotaxis to the ovum inside an oviduct . In assisted reproductive technology , normozoospermia
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#17327808264066944-470: The egg during fertilisation and starts the first cleavage division of the egg, which has no centriole. The distal centriole gives rise to the axial filament which forms the tail and has a (9+2) arrangement. A transitory membrane called the Manchette lies in the middle piece. Middle piece: It has 10–14 spirals of mitochondria surrounding the axial filament in the cytoplasm. It provides motility, and hence
7056-405: The female reproductive tract and are a means by which fertilization is promoted. The postmeiotic phase of mouse spermatogenesis is very sensitive to environmental genotoxic agents, because as male germ cells form mature spermatozoa they progressively lose the ability to repair DNA damage. Irradiation of male mice during late spermatogenesis can induce damage that persists for at least 7 days in
7168-677: The fertilizing spermatozoa, and disruption of maternal DNA double-strand break repair pathways increases spermatozoa-derived chromosomal aberrations. Treatment of male mice with melphalan , a bifunctional alkylating agent frequently employed in chemotherapy, induces DNA lesions during meiosis that may persist in an unrepaired state as germ cells progress through DNA repair-competent phases of spermatogenic development. Such unrepaired DNA damages in spermatozoa, after fertilization, can lead to offspring with various abnormalities. Sea urchins such as Arbacia punctulata are ideal organisms to use in sperm research, they spawn large numbers of sperm into
7280-506: The five had at least moderate facial acne , reached the erroneous conclusion that acne was a defining characteristic of XYY males. After learning that convicted mass murderer Richard Speck had been karyotyped, Telfer not only incorrectly assumed the acne-scarred Speck was XYY, but reached the false conclusion that Speck was the archetypical XYY male—or "supermale" as Telfer referred to XYY males outside of peer-reviewed scientific journals. In April 1968, The New York Times —using Telfer as
7392-586: The formation of sperm cells. An incident in chromosome separation during anaphase II (of meiosis II ) called nondisjunction can result in sperm cells with an extra copy of the Y-chromosome. If one of these atypical sperm cells contributes to the genetic makeup of a child, the child will have an extra Y-chromosome in each of the body's cells. In some cases, the extra Y-chromosome results from nondisjunction during mitosis in early embryonic development. This can produce 46,XY/47,XYY mosaics . 47,XYY syndrome
7504-403: The functional spermatozoa. The MMP (Million Motile Progressive cells per milliliter) measure is synonymous with capacitation , and is very useful parameter to decide, along with a spermiogram , the kind of treatment needed. it represents the ratio between the % of progressive motile sperm obtained in capacitated and the % of progressive motile sperm obtained in ejaculated. It is based on
7616-403: The fundamental unit of life is the cell, and not some preformed parts of an organism. Various hereditary mechanisms, including blending inheritance were also envisaged without being properly tested or quantified, and were later disputed. Nevertheless, people were able to develop domestic breeds of animals as well as crops through artificial selection. The inheritance of acquired traits also formed
7728-463: The gap between experimental geneticists and naturalists; and between both and palaeontologists, stating that: The idea that speciation occurs after populations are reproductively isolated has been much debated. In plants, polyploidy must be included in any view of speciation. Formulations such as 'evolution consists primarily of changes in the frequencies of alleles between one generation and another' were proposed rather later. The traditional view
7840-495: The government to abort XYY "sex deviants". Mischaracterization of the XYY genetic condition was quickly incorporated into high school biology textbooks and medical school psychiatry textbooks, where misinformation still persists decades later. In 1973, child psychiatrist Herbert Schreier at Children's Hospital told Harvard Medical School microbiologist Jon Beckwith of Science for the People that he thought Walzer's Boston XYY study
7952-430: The high level of DNA compaction in these cells, human spermatozoa possess a truncated base excision repair pathway that is mediated by 8-oxoguanine DNA glycosylase 1 (OGG1) . Thus mature spermatozoa appear to have a limited capacity to mount a DNA repair response to oxidative stress . Glycoprotein molecules on the surface of ejaculated sperm cells are recognized by all human female immune systems, and interpreted as
8064-415: The interaction between a person's genotype and sunlight; thus, suntans are not passed on to people's children. However, some people tan more easily than others, due to differences in their genotype: a striking example is people with the inherited trait of albinism , who do not tan at all and are very sensitive to sunburn . Heritable traits are known to be passed from one generation to the next via DNA ,
8176-416: The largest known spermatozoon found in nature. Drosophila melanogaster produces sperm that can be up to 1.8 mm, while its relative Drosophila bifurca produces the largest known spermatozoon, measuring over 58 mm in length. In Drosophila melanogaster , the entire sperm, tail included, gets incorporated into the oocyte cytoplasm , however, for Drosophila bifurca only a small portion of
8288-434: The laws of heredity through compiling data on family phenotypes (nose size, ear shape, etc.) and expression of pathological conditions and abnormal characteristics, particularly with respect to the age of appearance. One of the projects aims was to tabulate data to better understand why certain traits are consistently expressed while others are highly irregular. The idea of particulate inheritance of genes can be attributed to
8400-465: The lower intelligence of those with criminal convictions, but found no evidence that XXY or XYY men were inclined to be aggressive or violent. The March of Dimes sponsored five international conferences in June 1974, November 1977, May 1981, June 1984, and June 1989 and published articles from the conferences in book form in 1979, 1982, 1986, and 1991 from seven longitudinal prospective cohort studies on
8512-455: The male body the sperm's survival likelihood is reduced and it may die, thereby decreasing the total sperm quality . Sperm cells come in two types, "female" and "male". Sperm cells that give rise to female (XX) offspring after fertilization differ in that they carry an X-chromosome, while sperm cells that give rise to male (XY) offspring carry a Y-chromosome. A human sperm cell consists of a flat, disc shaped head 5.1 μm by 3.1 μm and
8624-490: The next generation were the womb in which the homunculus grew, and prenatal influences of the womb. An opposing school of thought, the ovists, believed that the future human was in the egg, and that sperm merely stimulated the growth of the egg. Ovists thought women carried eggs containing boy and girl children, and that the gender of the offspring was determined well before conception. An early research initiative emerged in 1878 when Alpheus Hyatt led an investigation to study
8736-630: The nuclei of interphase cells in buccal smears treated with quinacrine dihydrochloride, which could be used to screen for Y chromosome aneuploidies like 47,XYY. In December 1970, at the annual meeting of the American Association for the Advancement of Science (AAAS), its retiring president, geneticist H. Bentley Glass , cheered by the legalization of abortion in New York , envisioned a future where pregnant women would be required by
8848-452: The offspring cells or organisms acquire the genetic information of their parents. Through heredity, variations between individuals can accumulate and cause species to evolve by natural selection . The study of heredity in biology is genetics . In humans, eye color is an example of an inherited characteristic: an individual might inherit the "brown-eye trait" from one of the parents. Inherited traits are controlled by genes and
8960-458: The offspring is determined by the sperm cell: a spermatozoon bearing an X chromosome will lead to a female (XX) offspring, while one bearing a Y chromosome will lead to a male (XY) offspring. Sperm cells were first observed in Antonie van Leeuwenhoek 's laboratory in 1677. The human sperm cell is the reproductive cell in males and will only survive in warm environments; once it leaves
9072-427: The oocyte is said to have become activated . It undergoes its secondary meiotic division, and the two haploid nuclei (paternal and maternal) fuse to form a zygote . In order to prevent polyspermy and minimise the possibility of producing a triploid zygote, several changes to the egg's zona pellucida renders them impenetrable shortly after the first sperm enters the egg. Spermatozoa can be stored in diluents such as
9184-529: The ovary with the egg and support it as it grows. The initial change is called "hyperactivation", which causes a change in spermatozoa motility. They swim faster and their tail movements become more forceful and erratic. A recent discovery links hyperactivation to a sudden influx of calcium ion into the tails. The whip-like tail (flagellum) of the sperm is studded with ion channels formed by proteins called CatSper . These channels are selective, allowing only calcium ions to pass. The opening of CatSper channels
9296-400: The pair of alleles either GG (homozygote) or Gg (heterozygote) will have green pods. The allele for yellow pods is recessive. The effects of this allele are only seen when it is present in both chromosomes, gg (homozygote). This derives from Zygosity , the degree to which both copies of a chromosome or gene have the same genetic sequence, in other words, the degree of similarity of
9408-401: The paper," Getty said. Getty did say that a chromosomal test was performed on Speck, before Speck's trial, by a geneticist from outside the Chicago area. He declined to identify the geneticist, and he said the results of the test never have been disclosed. "It was agreed," he said, "that the results would not be disclosed unless I wished them disclosed. And I still don't." In any case, Getty said,
9520-412: The plasma membrane of the sperm's head, exposing the contents of the acrosome. Neck: It is the smallest part (.03 μm), and has a proximal centriole parallel to the base of the nucleus and distal centriole perpendicular to the previous one. The proximal centriole is present also in the mature spermatozoon; the distal centriole disappears after axoneme assembly. The proximal centriole enters into
9632-557: The recovery percentage. Depending on the percentage, we will decide the quality of the motile spermatozoa recovery: 15 to 25 million sperm/ml is considered optimal, between 5 and 15 million is considered enough and less than 5 million is considered sub-optimal or not sufficient. Regarding the values that we have obtained, along with the spermiogram results, different techniques will be displayed. For example, if more than 1.0×10 progressive motile sperm per milliliter are found, it will be recommended to have sexual intercourse, and if that fails,
9744-422: The rest of those diagnosed after birth, around half are diagnosed during childhood or adolescence after developmental delays are observed. The rest are diagnosed after any of a variety of symptoms, including fertility problems (5%) have been seen. Around 1 in 1,000 boys are born with a 47,XYY karyotype. The incidence of 47,XYY is not known to be affected by the parents' ages. In April 1956, Hereditas published
9856-471: The resulting two cells will inherit the DNA sequence. A portion of a DNA molecule that specifies a single functional unit is called a gene ; different genes have different sequences of bases. Within cells , the long strands of DNA form condensed structures called chromosomes . Organisms inherit genetic material from their parents in the form of homologous chromosomes , containing a unique combination of DNA sequences that code for genes. The specific location of
9968-454: The results could not be used in an appeal—since they were not part of the trial evidence. If anything, he said, they could only be used in connection with a new trial. At the same time he made public reports from Vanderbilt University showing no abnormal makeup of Speck's chromosomes... Getty displayed a letter of Sept. 26, 1966, relating that photographic evidence of 18 cells from Speck's blood showed no chromosome abnormality. He also exhibited
10080-591: The risk of aneuploid spermatozoa. In particular, risk of aneuploidy is increased by tobacco smoking, and occupational exposure to benzene, insecticides, and perfluorinated compounds. Increased aneuploidy of spermatozoa often occurs in association with increased DNA damage. DNA fragmentation and increased in situ DNA susceptibility to denaturation, the features similar to these seen during apoptosis of somatic cells, characterize abnormal spermatozoa in cases of male infertility . Although DNA repair has long been considered impossible in human spermatozoa due to
10192-422: The sea, making them well-suited as model organisms for experiments. The spermatozoa of marsupials are usually longer than those of placental mammals . The gametophytes of bryophytes , ferns and some gymnosperms produce motile sperm cells, contrary to pollen grains employed in most gymnosperms and all angiosperms . This renders sexual reproduction in the absence of water impossible, since water
10304-427: The selection regime of subsequent generations. Descendants inherit genes plus environmental characteristics generated by the ecological actions of ancestors. Other examples of heritability in evolution that are not under the direct control of genes include the inheritance of cultural traits , group heritability , and symbiogenesis . These examples of heritability that operate above the gene are covered broadly under
10416-508: The sex chromosome trisomies 47,XXX, 47,XXY, and 47,XYY. In July 1999, Psychological Medicine published a case-control study by Royal Edinburgh Hospital psychiatrist Michael Götz and colleagues that found an increased rate of criminal convictions among seventeen XYY men identified in the Edinburgh newborn screening study compared to an above-average-IQ control group of sixty XY men, which multiple logistic regression analysis indicated
10528-402: The sperm to fuse with the egg. ZP3, one of the proteins that make up the zona pellucida, then binds to a partner molecule on the sperm. Enzymes on the inner acrosomal membrane digest the zona pellucida. After the sperm penetrates the zona pellucida, part of the sperm's cell membrane then fuses with the egg cell's membrane, and the contents of the head diffuse into the egg. Upon penetration,
10640-589: The study's lack of informed consent . In the late 1960s and early 1970s, screening of consecutive newborns for sex chromosome abnormalities was undertaken at seven centers worldwide: in Denver (Jan 1964–1974), Edinburgh (Apr 1967–Jun 1979), New Haven (Oct 1967–Sep 1968), Toronto (Oct 1967–Sep 1971), Aarhus (Oct 1969–Jan 1974, Oct 1980–Jan 1989), Winnipeg (Feb 1970–Sep 1973), and Boston (Apr 1970–Nov 1974). The Boston study, led by Harvard Medical School child psychiatrist Stanley Walzer at Children's Hospital ,
10752-464: The surface membrane even in the case of human sperms. Mammalian sperm cells become even more active when they approach an egg cell in a process called sperm activation . Sperm activation has been shown to be caused by calcium ionophores in vitro , progesterone released by nearby cumulus cells and binding to ZP3 of the zona pellucida . The cumulus cells are embedded in a gel-like substance made primarily of hyaluronic acid , and developed in
10864-425: The tail enters the oocyte. The wood mouse Apodemus sylvaticus possesses spermatozoa with falciform morphology. Another characteristics which makes these gametocytes unique is the presence of an apical hook on the sperm head. This hook is used to attach to the hooks or to the flagella of other spermatozoa. Aggregation is caused by these attachments and mobile trains result. These trains provide improved motility in
10976-446: The three dimensional conformation of proteins (such as prions ) are areas where epigenetic inheritance systems have been discovered at the organismic level. Heritability may also occur at even larger scales. For example, ecological inheritance through the process of niche construction is defined by the regular and repeated activities of organisms in their environment. This generates a legacy of effect that modifies and feeds back into
11088-465: The title of multilevel or hierarchical selection , which has been a subject of intense debate in the history of evolutionary science. When Charles Darwin proposed his theory of evolution in 1859, one of its major problems was the lack of an underlying mechanism for heredity. Darwin believed in a mix of blending inheritance and the inheritance of acquired traits ( pangenesis ). Blending inheritance would lead to uniformity across populations in only
11200-403: The urge to violence may be inborn—traced to something called the Y chromosome... Once in every 500 male births, for example, the sex chromosome complement is XXY rather than XY, thus erring in the direction of femaleness. The resulting individual, called a Klinefelter male, is usually retarded, unusually tall and sterile. Erring in the other direction, however, is the XYY complement resulting in
11312-525: The young life sown within her". Ancient understandings of heredity transitioned to two debated doctrines in the 18th century. The Doctrine of Epigenesis and the Doctrine of Preformation were two distinct views of the understanding of heredity. The Doctrine of Epigenesis, originated by Aristotle , claimed that an embryo continually develops. The modifications of the parent's traits are passed off to an embryo during its lifetime. The foundation of this doctrine
11424-403: Was 174.1 cm (5 ft 8 + 1 ⁄ 2 in), their mothers' average height was 162.8 cm (5 ft 4 + 1 ⁄ 8 in). The increased gene dosage of three X/Y chromosome pseudoautosomal region (PAR1) SHOX genes has been postulated as a cause of the increased stature seen in all three sex chromosome trisomies: 47,XXX, 47,XXY, and 47,XYY. Severe acne was noted in
11536-614: Was adopted by, and then heavily modified by, his cousin Francis Galton , who laid the framework for the biometric school of heredity. Galton found no evidence to support the aspects of Darwin's pangenesis model, which relied on acquired traits. The inheritance of acquired traits was shown to have little basis in the 1880s when August Weismann cut the tails off many generations of mice and found that their offspring continued to develop tails. Scientists in Antiquity had
11648-435: Was an incidental finding in a normal 44-year-old, 6 ft. [183 cm] tall man of average intelligence who was karyotyped because he had a daughter with Down syndrome . Only a dozen isolated 47,XYY cases were reported in the medical literature in the four years following the first report by Sandberg. The XYY syndrome, if named after the discoverer, should rightly be termed Sandberg syndrome and not Jacobs syndrome although
11760-413: Was based on the theory of inheritance of acquired traits . In direct opposition, the Doctrine of Preformation claimed that "like generates like" where the germ would evolve to yield offspring similar to the parents. The Preformationist view believed procreation was an act of revealing what had been created long before. However, this was disputed by the creation of the cell theory in the 19th century, where
11872-515: Was directly responsible for stimulating a great deal of research in the post- World War II era. Trofim Lysenko however caused a backlash of what is now called Lysenkoism in the Soviet Union when he emphasised Lamarckian ideas on the inheritance of acquired traits . This movement affected agricultural research and led to food shortages in the 1960s and seriously affected the USSR. There
11984-1052: Was echoed the following week by articles—again using Telfer as a main source—in Time and Newsweek , and six months later in The New York Times Magazine . In December 1968, the Journal of Medical Genetics published the first XYY review article—by Willam Michael Court Brown (1918–1969), director of the MRC Human Genetics Unit—which reported that he had found no overrepresentation of XYY males in nationwide chromosome surveys of prisons and hospitals for developmentally disabled and mentally ill people in Scotland, and concluded that studies confined to institutionalized XYY males may be guilty of selection bias , and that long-term longitudinal prospective studies of newborn XYY boys were needed. In May 1969, at
12096-486: Was mediated mainly through lowered intelligence. In June 2002, the American Journal of Medical Genetics published results from a longitudinal prospective cohort Denver Family Development Study led by pediatrician and geneticist Arthur Robinson, which found that in fourteen prenatally diagnosed 47,XYY boys (from high socioeconomic status families), IQ scores available for six boys ranged from 100 to 147 with
12208-682: Was not reduced compared to the general population. In a summary of six prospective studies of 47,XYY boys identified by newborn screening programmes, twenty-eight 47,XYY boys had an average 100.76 verbal IQ , 108.79 performance IQ , and 105.00 full-scale IQ . In a systematic review including two prospective studies of 47,XYY boys identified by newborn screening programs and one retrospective study of 47,XYY men identified by screening men over 184 cm (6 ft 1 ⁄ 2 in) in height, forty-two 47,XYY boys and men had an average 99.5 verbal IQ and 106.4 performance IQ. In prospective studies of 47,XYY boys identified by newborn screening programs,
12320-469: Was published—the first of seven Kenneth Royce spy novels whose fictional tall, intelligent, nonviolent XYY hero was a reformed expert cat burglar recruited by British intelligence for dangerous assignments—and later adapted into a thirteen-episode British summer television series broadcast in 1976 and 1977. In other fictional television works, a January 1971 episode "By the Pricking of My Thumbs ..." of
12432-453: Was unethical; Science for the People investigated the study and, regarding the study, filed an ethics complaint with Harvard Medical School in March 1974. In November 1974, Science for the People went public with their objections to the Boston XYY study in a press conference and a New Scientist article alleging inadequate informed consent, a lack of benefit (since no specific treatment was available) but substantial risk (by stigmatization with
12544-464: Was unique among the seven newborn screening studies in that it only screened newborn boys (non-private-ward newborn boys at the Boston Hospital for Women ) and was funded in part by grants from the NIMH Center for Studies of Crime and Delinquency. The Edinburgh study was led by Shirley Ratcliffe who focused her career on it and published the results in 1999. In December 1969, Lore Zech at
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