Evolution: From Autosomes to Sex Chromosomes — and Back
نویسندگان
چکیده
Heteromorphic sex chromosomes are thought to represent a terminal evolutionary endpoint due to their specialized gene content and chromosome-specific regulation. New findings, however, show that an ancient X chromosome reverted to an autosome in the lineage leading to Drosophila.
منابع مشابه
Genomic changes following the reversal of a Y chromosome to an autosome in Drosophila pseudoobscura
Robertsonian translocations resulting in fusions between sex chromosomes and autosomes shape karyotype evolution by creating new sex chromosomes from autosomes. These translocations can also reverse sex chromosomes back into autosomes, which is especially intriguing given the dramatic differences between autosomes and sex chromosomes. To study the genomic events following a Y chromosome reversa...
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The sex chromosomes offer a genetic apparatus involved in the sex determination in many dioecious organisms. There can be heterogametically defined males and homogametically defined females (the X–Y systems, e.g. humans and Drosophila) or vice versa as heterogametically females and homogametically males (the Z–W systems, e.g. chickens and silkworms). The origin and evolution of sex chromosomes ...
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عنوان ژورنال:
- Current Biology
دوره 23 شماره
صفحات -
تاریخ انتشار 2013