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The Evolution of Sex Chromosomes
Science, 1991Structurally distinct sex chromosomes (X and Y) are the most familiar mode of genetic sex determination and have evolved independently in many different taxa. The evolutionary paths by which their characteristic properties may have evolved are reviewed.
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The evolution of sex chromosomes
Cytogenetic and Genome Research, 2002Mammalian sex chromosomes appear, behave and function differently than the autosomes, passing on their genes in a unique sex-linked manner. The publishing of Ohno’s hypothesis provided a framework for discussion of sex chromosome evolution, allowing it to be developed and challenged numerous times. In this report we discuss the pressures that drove the
L.J. Ayling, Darren K. Griffin
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Archiv für Mikroskopische Anatomie, 1911
The problem of sex-determination has been examined by three principal methods, (1) by experiments on the influence of external conditions as affecting the germ, (2) by experiments on the heredity of sex and of sex-limited characters, (3) by microscopical examination of the germ-cells.
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The problem of sex-determination has been examined by three principal methods, (1) by experiments on the influence of external conditions as affecting the germ, (2) by experiments on the heredity of sex and of sex-limited characters, (3) by microscopical examination of the germ-cells.
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Sex chromosomes and sex determination in reptiles
Current Opinion in Genetics & Development, 2005Reptiles occupy a crucial position with respect to vertebrate phylogeny, having roamed the earth for more than 300 million years and given rise to both birds and mammals. To date, this group has been largely ignored by contemporary genomics technologies, although the green anole lizard was recently recommended for whole genome sequencing.
David Crews, William S. Modi
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2015
With the ability to see individual chromosomes, it becomes apparent that there is a difference at the cellular level between males and females; not only that but it becomes possible to explain some of the observations that were made prior to knowing the chromosome number. One such case is the Barr body.
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With the ability to see individual chromosomes, it becomes apparent that there is a difference at the cellular level between males and females; not only that but it becomes possible to explain some of the observations that were made prior to knowing the chromosome number. One such case is the Barr body.
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Sex Chromosomes and Sex Determination in Lepidoptera
Sexual Development, 2007The speciose insect order Lepidoptera (moths and butterflies) and their closest relatives, Trichoptera (caddis flies), share a female-heterogametic sex chromosome system. Originally a Z/ZZ (female/male) system, it evolved by chromosome rearrangement to a WZ/ZZ (female/male) system in the most species-rich branch of Lepidoptera, a monophyletic group ...
Walther Traut +2 more
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New England Journal of Medicine, 1976
The sex chromosome abnormalities are one of the most common types of chromosome disorders, occurring once among every 1100 females and once among every 380 males.
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The sex chromosome abnormalities are one of the most common types of chromosome disorders, occurring once among every 1100 females and once among every 380 males.
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Sex Determination and Sex Chromosomes in Amphibia
Sexual Development, 2017Sex chromosomes in most amphibians are homomorphic (undifferentiated) in both sexes and are characterized by frequent turnover. This is in sharp contrast to sex chromosomes in 2 major vertebrate groups, the mammals and birds, where they are heteromorphic in one sex and are highly conserved.
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Sex Chromosomes in Macromitrium [PDF]
The Bryologist, 1966 Chromosome numbers of n = 8, 9, and 11 have been found in the five species of Macromitrium examined. Evidence is presented in support of an X/Y sex chromosome mechanism in which the X chromosome is larger than the Y. These morphologically distinct chromosomes occur in dioecious species having chromosome numbers of n = 8 and n = 9 and form a dimolphic ...
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