Misplaced Pages

#184815

67-526: " Twin Sisters " may refer to: Female twins Arts and entertainment [ edit ] Twin Sisters (1934 film) , a Chinese film Twin Sisters (2002 film) , or De tweeling , a Dutch film Twin Sisters (2013 film) , a Norwegian documentary Twin Sisters of Kyoto , a 1963 Japanese drama film Mr Twin Sister , an American band Places in

134-445: A disorders of the reproductive system . If the egg fails to release from the follicle in the ovary an ovarian cyst may form. Small ovarian cysts are common in healthy women. Some women have more follicles than usual ( polycystic ovary syndrome ), which inhibits the follicles to grow normally and this will cause cycle irregularities. the ovaries. Cryopreservation of ovarian tissue, often called ovarian tissue cryopreservation ,

201-497: A greater chance of dizygotic multiple births. In the United States it has been estimated that by 2011 36% of twin births resulted from conception by assisted reproductive technology . The risk of twin birth can vary depending on what types of fertility treatments are used. With in vitro fertilisation (IVF), this is primarily due to the insertion of multiple embryos into the uterus. Ovarian hyperstimulation without IVF has

268-475: A key role in a type of DNA repair termed homologous recombinational repair that is the only known cellular process that can accurately repair DNA double-strand breaks. Titus et al. showed that DNA double-strand breaks accumulate with age in humans and mice in primordial follicles. Primordial follicles contain oocytes that are at an intermediate (prophase I) stage of meiosis. Meiosis is the general process in eukaryotic organisms by which germ cells are formed, and it

335-506: A more likely explanation. A high twinning rate has also been observed in other places of the world, including: The widespread use of fertility drugs causing hyperovulation (stimulated release of multiple eggs by the mother) has caused what some call an "epidemic of multiple births ". In 2001, for the first time ever in the US , the twinning rate exceeded 3% of all births. Nevertheless, the rate of monozygotic twins remains at about 1 in 333 across

402-460: A pair of monozygotic twins reproduces with another pair or with the same person), rather than first cousins. Identical twins do not have the same fingerprints however, because even within the confines of the womb, the fetuses touch different parts of their environment, giving rise to small variations in their corresponding prints and thus making them unique. Monozygotic twins always have the same genotype . Normally due to an environmental factor or

469-545: A rate of about 3 in every 1000 deliveries worldwide. The likelihood of a single fertilization resulting in monozygotic twins is uniformly distributed in all populations around the world. This is in marked contrast to dizygotic twinning, which ranges from about six per thousand births in Japan (almost similar to the rate of identical twins, which is around 4–5) to 15 and more per thousand in some parts of India and up to over 20 in some Central African countries. The exact cause for

536-406: A separate fetus, rather than by the embryo splitting while hatching from the zona pellucida (the gelatinous protective coating around the blastocyst). Monozygotic twins may also be created artificially by embryo splitting. It can be used as an expansion of in vitro fertilization (IVF) to increase the number of available embryos for embryo transfer . Monozygotic twinning occurs in birthing at

603-541: A study in 2012 found that it is possible for a polar body to result in a healthy fetus. In 2003, a study argued that many cases of triploidy arise from sesquizygotic (semi-identical) twinning which happens when a single egg is fertilized by two sperm and splits the three sets of chromosomes into two separate cell sets. The degree of separation of the twins in utero depends on if and when they split into two zygotes. Dizygotic twins were always two zygotes. Monozygotic twins split into two zygotes at some time very early in

670-451: A very different way in most invertebrates than they do in vertebrates, and are not truly homologous. Many of the features found in human ovaries are common to all vertebrates, including the presence of follicular cells, tunica albuginea, and so on. However, many species produce a far greater number of eggs during their lifetime than do humans, so that, in fish and amphibians, there may be hundreds, or even millions of fertile eggs present in

737-478: A very high risk of multiple birth. Reversal of anovulation with clomifene (trade names including Clomid ) has a relatively less but yet significant risk of multiple pregnancy. A 15-year German study of 8,220 vaginally delivered twins (that is, 4,110 pregnancies) in Hesse yielded a mean delivery time interval of 13.5 minutes. The delivery interval between the twins was measured as follows: The study stated that

SECTION 10

#1732772362185

804-412: A woman's ovaries as "female testes". Birds have only one functional ovary (the left), while the other remains vestigial. In mammals including humans, the female ovary is homologous to the male testicle , in that they are both gonads and endocrine glands . Ovaries of some kind are found in the female reproductive system of many invertebrates that employ sexual reproduction . However, they develop in

871-557: Is a genetically linked tendency to hyper- ovulate . There is no known genetic link for identical twinning. Other factors that increase the odds of having fraternal twins include maternal age, fertility drugs and other fertility treatments, nutrition, and prior births. Some women intentionally turn to fertility drugs in order to conceive twins. The vast majority of twins are either dizygotic (fraternal) or monozygotic (identical). In humans dizygotic twins occur more often than monozygotic twins. Less common variants are discussed further down

938-493: Is different from Wikidata All article disambiguation pages All disambiguation pages Twin In contrast, a fetus that develops alone in the womb (the much more common case in humans) is called a singleton , and the general term for one offspring of a multiple birth is a multiple . Unrelated look-alikes whose resemblance parallels that of twins are referred to as doppelgänger . The human twin birth rate in

1005-446: Is fertilized to form one zygote (hence, "monozygotic") which then divides into two separate embryos . The chances of having identical twins is relatively rare – around 3 or 4 in every 1,000 births. Regarding spontaneous or natural monozygotic twinning, a 2007 theory related to in vitro fertilization (IVF) proposes that monozygotic twins may be formed when a blastocyst contains two inner cell masses (ICM), each of which will lead to

1072-412: Is likely an adaptation for removing DNA damages, especially double-strand breaks, from germ line DNA (see Meiosis and Origin and function of meiosis ). Homologous recombinational repair is especially promoted during meiosis. Titus et al. also found that expression of 4 key genes necessary for homologous recombinational repair of DNA double-strand breaks (BRCA1, MRE11, RAD51 and ATM) decline with age in

1139-415: Is not the case in all species. In most birds and in platypuses , the right ovary never matures, so that only the left is functional. (Exceptions include the kiwi and some, but not all raptors , in which both ovaries persist. ) In some elasmobranchs, only the right ovary develops fully. In the primitive jawless fish , and some teleosts, there is only one ovary, formed by the fusion of the paired organs in

1206-408: Is of interest to women who want to preserve their reproductive function beyond the natural limit, or whose reproductive potential is threatened by cancer therapy, for example in hematologic malignancies or breast cancer. The procedure is to take a part of the ovary and carry out slow freezing before storing it in liquid nitrogen whilst therapy is undertaken. Tissue can then be thawed and implanted near

1273-473: Is produced by the ovaries and released directly into the blood stream. The other 50% of testosterone in the blood stream is made from conversion of the adrenal pre-androgens ( DHEA and androstenedione) to testosterone in other parts of the body. Estrogen is responsible for the appearance of secondary sex characteristics for females at puberty and for the maturation and maintenance of the reproductive organs in their mature functional state. Progesterone prepares

1340-419: Is the most common type of twin. Dizygotic twins, like any other siblings, will practically always have different sequences on each chromosome, due to chromosomal crossover during meiosis . Dizygotic twins share on average 50 percent of each other's genes, the same as siblings that are conceived and born at different times. Like any other siblings , dizygotic twins may look similar , particularly as they are

1407-683: The Yoruba to 10% for Linha São Pedro, a tiny Brazilian settlement which belongs to the city of Cândido Godói . In Cândido Godói, one in five pregnancies has resulted in twins. The Argentine historian Jorge Camarasa has put forward the theory that experiments of the Nazi doctor Josef Mengele could be responsible for the high ratio of twins in the area. His theory was rejected by Brazilian scientists who had studied twins living in Linha São Pedro; they suggested genetic factors within that community as

SECTION 20

#1732772362185

1474-462: The blastocysts have fused. Monochorionic twins share the same placenta , and thus have a risk of twin-to-twin transfusion syndrome . Monoamniotic twins are always monozygotic . The survival rate for monoamniotic twins is somewhere between 50% and 60%. Monoamniotic twins, as with diamniotic monochorionic twins, have a risk of twin-to-twin transfusion syndrome . Also, the two umbilical cords have an increased chance of being tangled around

1541-408: The fallopian tube / oviduct into the uterus . There is an ovary on the left and the right side of the body. The ovaries are endocrine glands , secreting various hormones that play a role in the menstrual cycle and fertility . The ovary progresses through many stages beginning in the prenatal period through menopause . Each ovary is whitish in color and located alongside the lateral wall of

1608-431: The mesovarium . The ovarian pedicle is made up part of the fallopian tube , mesovarium , ovarian ligament, and ovarian blood vessels. The surface of the ovaries is covered with a membrane consisting of a lining of simple cuboidal -to-columnar shaped mesothelium , called the germinal epithelium . The outer layer is the ovarian cortex , consisting of ovarian follicles and stroma in between them. Included in

1675-407: The tunica albuginea . Usually, ovulation occurs in one of the two ovaries releasing an egg each menstrual cycle . The side of the ovary closest to the fallopian tube is connected to it by infundibulopelvic ligament , and the other side points downwards attached to the uterus via the ovarian ligament . Other structures and tissues of the ovaries include the hilum . The ovaries lie within

1742-406: The uterus in a region called the ovarian fossa . The ovarian fossa is the region that is bounded by the external iliac artery and in front of the ureter and the internal iliac artery . This area is about 4 cm x 3 cm x 2 cm in size. The ovaries are surrounded by a capsule, and have an outer cortex and an inner medulla. The capsule is of dense connective tissue and is known as

1809-1119: The United States [ edit ] Twin Sisters, Texas Twin Sisters (California) , twin summits of a mountain Twin Sisters (Colorado) , a mountain summit Twin Sisters Peaks , mountains in Colorado Twin Sisters Mountain , in Washington Twin Sisters Basalt, a pillar near Wallula Gap , Washington Other uses [ edit ] Twin Sisters (cannons) , from the Texas Revolution See also [ edit ] All pages with titles beginning with Twin Sisters All pages with titles containing Twin Sisters Twin (disambiguation) Twins (disambiguation) Topics referred to by

1876-560: The United States rose 76% from 1980 through 2009, from 9.4 to 16.7 twin sets (18.8 to 33.3 twins) per 1,000 births. The Yoruba people have the highest rate of twinning in the world, at 45–50 twin sets (90–100 twins) per 1,000 live births, possibly because of high consumption of a specific type of yam containing a natural phytoestrogen which may stimulate the ovarys to release an egg from each side. In Central Africa , there are 18–30 twin sets (or 36–60 twins) per 1,000 live births. In South America , South Asia , and Southeast Asia ,

1943-514: The article. Fraternal twins can be any of the following: Among non-twin births, male singletons are slightly (about five percent) more common than female singletons. The rates for singletons vary slightly by country. For example, the sex ratio of birth in the US is 1.05 males/female, while it is 1.07 males/female in Italy. However, males are also more susceptible than females to die in utero , and since

2010-473: The babies. Because of this, there is an increased chance that the newborns may be miscarried or suffer from cerebral palsy due to lack of oxygen. When the division of the developing zygote into 2 embryos occurs, 99% of the time it is within 8 days of fertilization. Mortality is highest for conjoined twins due to the many complications resulting from shared organs. A 2006 study has found that insulin-like growth factor present in dairy products may increase

2077-469: The central part of the ovary is a hollow, lymph -filled space. The ovary of teleosts is also often hollow, but in this case, the eggs are shed into the cavity, which opens into the oviduct . Certain nematodes of the genus Philometra are parasitic in the ovary of marine fishes and can be spectacular, with females as long as 40 cm (16 in), coiled in the ovary of a fish half this length. Although most female vertebrates have two ovaries, this

Twin Sisters - Misplaced Pages Continue

2144-450: The chance of dizygotic twinning. Specifically, the study found that vegan mothers (who exclude dairy from their diets) are one-fifth as likely to have twins as vegetarian or omnivore mothers, and concluded that "Genotypes favoring elevated IGF and diets including dairy products, especially in areas where growth hormone is given to cattle, appear to enhance the chances of multiple pregnancies due to ovarian stimulation." From 1980 to 1997,

2211-513: The cortex and medulla, but follicles are usually not found in the medulla. Follicular cells are flat epithelial cells that originate from surface epithelium covering the ovary. They are surrounded by granulosa cells that have changed from flat to cuboidal and proliferated to produce a stratified epithelium. The ovary also contains blood vessels and lymphatics . At puberty , the ovary begins to secrete increasing levels of hormones. Secondary sex characteristics begin to develop in response to

2278-406: The deactivation of different X chromosomes in female monozygotic twins, and in some extremely rare cases, due to aneuploidy , twins may express different sexual phenotypes , normally from an XXY Klinefelter syndrome zygote splitting unevenly. Monozygotic twins, although genetically very similar, are not genetically exactly the same. The DNA in white blood cells of 66 pairs of monozygotic twins

2345-413: The death rate in utero is higher for twins, it leads to female twins being more common than male twins. Zygosity is the degree of identity in the genome of twins. Dizygotic ( DZ ) or fraternal twins (also referred to as "non-identical twins", "dissimilar twins", "biovular twins", and, informally in the case of females, "sororal twins") usually occur when two fertilized eggs are implanted in

2412-408: The differences detected in this study would have occurred during embryonic cell-division (after the point of fertilization). If they occur early in fetal development, they will be present in a very large proportion of body cells. Another cause of difference between monozygotic twins is epigenetic modification , caused by differing environmental influences throughout their lives. Epigenetics refers to

2479-405: The early stages of embryonic development. A 1981 study of a deceased XXX twin fetus without a heart showed that although its fetal development suggested that it was an identical twin, as it shared a placenta with its healthy twin, tests revealed that it was probably a polar body twin. The authors were unable to predict whether a healthy fetus could result from a polar body twinning. However,

2546-687: The epigenetic difference of three-year-old twins. Twins who had spent their lives apart (such as those adopted by two different sets of parents at birth) had the greatest difference. However, certain characteristics become more alike as twins age, such as IQ and personality. In January 2021, new research from a team of researchers in Iceland was published in the journal Nature Genetics suggesting that identical twins may not be quite as identical as previously thought. The four-year study of monozygotic (identical) twins and their extended families revealed that these twins have genetic differences that begin in

2613-535: The fallopian, either orthotopic (on the natural location) or heterotopic (on the abdominal wall), where it starts to produce new eggs, allowing normal conception to take place. A study of 60 procedures concluded that ovarian tissue harvesting appears to be safe. The ovarian tissue may also be transplanted into mice that are immunocompromised ( SCID mice ) to avoid graft rejection , and tissue can be harvested later when mature follicles have developed. In former centuries, medical authors, for example Galen , referred to

2680-438: The fluid-filled follicles . Typically, only one oocyte develops at a time, but others can also mature simultaneously. Follicles are composed of different types and number of cells according to the stage of their maturation , and their size is indicative of the stage of oocyte development. When an oocyte completes its maturation in the ovary, a surge of luteinizing hormone is secreted by the pituitary gland , which stimulates

2747-403: The follicles are the cumulus oophorus , membrana granulosa (and the granulosa cells inside it), corona radiata , zona pellucida , and primary oocyte . Theca of follicle , antrum and liquor folliculi are also contained in the follicle. Also in the cortex is the corpus luteum derived from the follicles. The innermost layer is the ovarian medulla . It can be hard to distinguish between

Twin Sisters - Misplaced Pages Continue

2814-480: The globe. In a study on the maternity records of 5750 Hausa women living in the Savannah zone of Nigeria , there were 40 twins and 2 triplets per 1000 births. Twenty-six percent of twins were monozygotic. The incidence of multiple births, which was about five times higher than that observed in any western population, was significantly lower than that of other ethnic groups, who live in the hot and humid climate of

2881-400: The hormones. The ovary changes structure and function beginning at puberty. Since the ovaries are able to regulate hormones, they also play an important role in pregnancy and fertility . When egg cells (oocytes) are released from the fallopian tube, a variety of feedback mechanisms stimulate the endocrine system, which cause hormone levels to change. These feedback mechanisms are controlled by

2948-403: The hypothalamus and pituitary glands. Messages or signals from the hypothalamus are sent to the pituitary gland. In turn, the pituitary gland releases hormones to the ovaries. From this signaling, the ovaries release their own hormones. The ovaries are the site of production and periodical release of egg cells , the female gametes. In the ovaries, the developing egg cells (or oocytes ) mature in

3015-536: The level of activity of any particular gene. A gene may become switched on, switched off, or could become partially switched on or off in an individual. This epigenetic modification is triggered by environmental events. Monozygotic twins can have markedly different epigenetic profiles. A study of 80 pairs of monozygotic twins ranging in age from three to 74 showed that the youngest twins have relatively few epigenetic differences. The number of epigenetic differences increases with age. Fifty-year-old twins had over three times

3082-406: The lowest mortality risk at about 9 percent, although that is still significantly higher than that of singletons. Monochorionic twins generally have two amniotic sacs (called Monochorionic–Diamniotic "MoDi"), which occurs in 60–70% of the pregnancies with monozygotic twins, and in 0.3% of all pregnancies. Monochorionic-Diamniotic twins are almost always monozygotic, with a few exceptions where

3149-459: The lowest rates are found; only 6 to 9 twin sets per 1,000 live births. North America and Europe have intermediate rates of 9 to 16 twin sets per 1,000 live births. Multiple pregnancies are much less likely to carry to full term than single births, with twin pregnancies lasting on average 37 weeks, three weeks less than full term. Women who have a family history of fraternal twins have a higher chance of producing fraternal twins themselves, as there

3216-573: The menstrual cycle begins to change and the follicle pool decreases significantly. The events that lead to ovarian aging remain unclear. The variability of aging could include environmental factors, lifestyle habits or genetic factors. Women with an inherited mutation in the DNA repair gene BRCA1 undergo menopause prematurely, suggesting that naturally occurring DNA damages in oocytes are repaired less efficiently in these women, and this inefficiency leads to early reproductive failure. The BRCA1 protein plays

3283-525: The number of twin births in the United States rose 52%. This rise can at least partly be attributed to the increasing popularity of fertility drugs and procedures such as IVF, which result in multiple births more frequently than unassisted fertilizations do. It may also be linked to the increase of growth hormones in food. About 1 in 90 human births (1.1%) results from a twin pregnancy. The rate of dizygotic twinning varies greatly among ethnic groups , ranging as high as about 45 per 1000 births (4.5%) for

3350-414: The occurrence of complications "was found to be more likely with increasing twin-to-twin delivery time interval" and suggested that the interval be kept short, though it noted that the study did not examine causes of complications and did not control for factors such as the level of experience of the obstetrician, the wish of the women giving birth, or the "management strategies" of the procedure of delivering

3417-484: The oocytes of humans and mice. They hypothesized that DNA double-strand break repair is vital for the maintenance of oocyte reserve and that a decline in efficiency of repair with age plays a key role in ovarian aging. A study identified 290 genetic determinants of ovarian ageing, also found that DNA damage response processes are implicated and suggests that possible effects of extending fertility in women would improve bone health, reduce risk of type 2 diabetes and increase

SECTION 50

#1732772362185

3484-469: The ovary at any given time. In these species, fresh eggs may be developing from the germinal epithelium throughout life. Corpora lutea are found only in mammals, and in some elasmobranch fish; in other species, the remnants of the follicle are quickly resorbed by the ovary. In birds, reptiles, and monotremes , the egg is relatively large, filling the follicle, and distorting the shape of the ovary at maturity. Amphibians and reptiles have no ovarian medulla;

3551-409: The peritoneal cavity, on either side of the uterus, to which they are attached via a fibrous cord called the ovarian ligament . The ovaries are uncovered in the peritoneal cavity but are tethered to the body wall via the suspensory ligament of the ovary , which is a posterior extension of the broad ligament of the uterus. The part of the broad ligament of the uterus that covers the ovary is known as

3618-473: The pregnancy. The timing of this separation determines the chorionicity (the number of placentae) and amniocity (the number of sacs) of the pregnancy. Dichorionic twins either never divided (i.e.: were dizygotic) or they divided within the first 4 days. Monoamnionic twins divide after the first week. In very rare cases, twins become conjoined twins . Non-conjoined monozygotic twins form up to day 14 of embryonic development, but when twinning occurs after 14 days,

3685-408: The rate of monozygotic twins) to 14 and more per thousand in some African countries. Dizygotic twins are also more common for older mothers, with twinning rates doubling in mothers over the age of 35. With the advent of technologies and techniques to assist women in getting pregnant, the rate of fraternals has increased markedly. Monozygotic ( MZ ) or identical twins occur when a single egg

3752-413: The release of the oocyte through the rupture of the follicle, a process called ovulation . The follicle remains functional and reorganizes into a corpus luteum , which secretes progesterone in order to prepare the uterus for an eventual implantation of the embryo. At maturity, ovaries secrete estrogen , androgen , inhibin , and progestogen . In women before menopause, 50% of testosterone

3819-467: The rest do not ovulate. The decline in ovarian reserve appears to occur at a constantly increasing rate with age, and leads to nearly complete exhaustion of the reserve by about age 52. As ovarian reserve and fertility decline with age, there is also a parallel increase in pregnancy failure and meiotic errors resulting in chromosomally abnormal conceptions. The ovarian reserve and fertility perform optimally around 20–30 years of age. Around 45 years of age,

3886-504: The risk of hormone-sensitive cancers. A variety of testing methods can be used in order to determine fertility based on maternal age. Many of these tests measure levels of hormones FSH, and GnrH. Methods such as measuring AMH ( anti-Müllerian hormone ) levels, and AFC (antral follicule count) can predict ovarian aging. AMH levels serve as an indicator of ovarian aging since the quality of ovarian follicles can be determined. Ovarian diseases can be classified as endocrine disorders or as

3953-444: The same age. However, dizygotic twins may also look very different from each other (for example, be of opposite sexes). Studies show that there is a genetic proclivity for dizygotic twinning. However, it is only the mother who has any effect on the chances of having such twins; there is no known mechanism for a father to cause the release of more than one ovum . Dizygotic twinning ranges from six per thousand births in Japan (similar to

4020-421: The same term [REDACTED] This disambiguation page lists articles associated with the title Twin Sisters . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Twin_Sisters&oldid=1048517614 " Category : Disambiguation pages Hidden categories: Short description

4087-546: The second twin. There have also been cases in which twins are born a number of days apart. Possibly the worldwide record for the duration of the time gap between the first and the second delivery was the birth of twins 97 days apart in Cologne, Germany, the first of which was born on November 17, 2018. Ovary The ovary (from Latin ōvārium  'egg') is a gonad in the female reproductive system that produces ova ; when released, an ovum travels through

SECTION 60

#1732772362185

4154-455: The southern part of the country. The incidence of multiple births was related to maternal age but did not bear any association to the climate or prevalence of malaria . Twins are more common in people of African descent. The predisposing factors of monozygotic twinning are unknown. Dizygotic twin pregnancies are slightly more likely when the following factors are present in the woman: Women undergoing certain fertility treatments may have

4221-414: The splitting of a zygote or embryo is unknown. IVF techniques are more likely to create dizygotic twins. For IVF deliveries, there are nearly 21 pairs of twins for every 1,000. Monozygotic twins are genetically nearly identical and they are the same chromosomal sex unless there has been a mutation during development. The children of monozygotic twins test genetically as half-siblings (or full siblings, if

4288-436: The twins will likely be conjoined. Furthermore, there can be various degrees of shared environment of twins in the womb, potentially leading to pregnancy complications . It is a common misconception that two placentas automatically implies dizygotic twins, but if monozygotic twins separate early enough, the arrangement of sacs and placentas in utero is in fact indistinguishable from that of dizygotic twins. DiDi twins have

4355-452: The uterus for pregnancy, and the mammary glands for lactation. Progesterone functions with estrogen by promoting menstrual cycle changes in the endometrium . As women age, they experience a decline in reproductive performance leading to menopause . This decline is tied to a decline in the number of ovarian follicles. Although about 1 million oocytes are present at birth in the human ovary, only about 500 (about 0.05%) of these ovulate, and

4422-466: The uterus wall at the same time. When two eggs are independently fertilized by two different sperm cells , fraternal twins result. The two eggs, or ova , form two zygotes , hence the terms dizygotic and biovular . Fraternal twins are, essentially, two ordinary siblings who happen to develop in the womb together and who are born at the same time, since they arise from two separate eggs fertilized by two separate sperm , just like ordinary siblings. This

4489-420: Was analyzed for 506,786 single-nucleotide polymorphisms known to occur in human populations. Polymorphisms appeared in 2 of the 33 million comparisons, leading the researchers to extrapolate that the blood cells of monozygotic twins may have on the order of one DNA-sequence difference for every 12 million nucleotides, which would imply hundreds of differences across the entire genome. The mutations producing

#184815