Morphologically undifferentiated intercourse chromosomes have now been described in lot of organisms, like the medaka seafood (28–30) then papaya (31). Your Y chromosome for the medaka is wholly homologous towards its counterpart with the exception of a 250-kb male-specific chromosomal area containing your male-determining DMY/DMRT1Yb gene (28–30).
Chulucanas That the region that is male-specific of papaya Y chromosome makes up ?10% of chromosome (31). Such cases lead people inside guess that each region that is differentiated your Z plus W chromosome concerning P. Molurus, and perhaps have sex-determining gene(s), is just too limited become detected through banding strategies to relative SEAFOOD mapping. As part of E. Quadrivirgata to T. Flavoviridis, their quick supply associated with W chromosome are thoroughly degenerated, plus very little homology between your Z to W chromosomes continues to be with the exclusion concerning the telomeric areas, where in fact the BamHI perform element try localized. Homology to your Z chromosome was partially preserved in the area nearby the centromere from the very long arm for the heterochromatic W chromosome at E. Quadrivirgata, while little homology regarding the prolonged supply is detected between the Z plus W chromosomes inside T. Flavoviridis. All effects claim that their differentiation out of intercourse chromosomes is initiated stperrting the distal area in the quick arm for the protosex chromosome when you look at the frequent ancestor through event to the intercourse differentiator at only 1 out of a autosomal set. That the cessation to meiotic recombination as a result of chromosome rearrangements happenatg into the sex-specific area is actually thought to prefer your accumulation to gene mutations. Your accumulation if resulted in partial removal out of euchromatic areas as well as heterochromatization utilizing the accumulation concerning repetitive DNA sequences on sex-specific chromosome, such as for instance extensive through the quick supply into the longer supply for the W chromosome into the E. Read More