The endemic cichlid fishes in Lake Victoria are a model system for speciation through adaptive radiation. Although the evolution of the sex-determination system may also play a role in speciation, little is known about the sex-determination system of Lake Victoria cichlids. To understand the evolution of the sex-determination system in these fish, we performed cytogenetic analysis in 11 cichlid...

The aim of the study was to determine sex fetus in gene expression data lacking this information using Y-linked genes, and elucidate difference between sex-chromosomal-linked placental samples with XX XY genotypes during pregnacy. We have detected 27 differentially expressed sex-chromosomes-linked genes. shown that, most cases, genes from X-chromosomes pregnancy carrying baby girls is higher th...

In most eutherian mammals, sex chromosomes synapse and recombine during male meiosis in a small region called pseudoautosomal region. However in some species sex chromosomes do not synapse, and how these chromosomes manage to ensure their proper segregation is under discussion. Here we present a study of the meiotic structure and behavior of sex chromosomes in one of these species, the Mongolia...

The Y or W sex chromosome of a heteromorphic pair is usually heterochromatinised and degenerated. However, whether degeneration constantly proceeds toward an extreme end not fully understood. Here, we present case intermittent evolution chromosomes caused by interpopulation hybridisation in the Japanese soil-frog, Glandirana rugosa. This species includes two systems, which are separated into ge...

Snakes exhibit genetic sex determination, with female heterogametic sex chromosomes (ZZ males, ZW females). Extensive cytogenetic work has suggested that the level of sex chromosome heteromorphism varies among species, with Boidae having entirely homomorphic sex chromosomes, Viperidae having completely heteromorphic sex chromosomes, and Colubridae showing partial differentiation. Here, we take ...

Recent progress of chicken genome projects has revealed that bird ZW and mammalian XY sex chromosomes were derived from different autosomal pairs of the common ancestor; however, the evolutionary relationship between bird and reptilian sex chromosomes is still unclear. The Chinese soft-shelled turtle (Pelodiscus sinensis) exhibits genetic sex determination, but no distinguishable (heteromorphic...