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[Evolution and mutation of human Y chromosome and their relationship with male infertility].

The Y chromosome evolves from euchromosome and accumulates a variety of male-specific genes, including SRY and many others that are related with spermatogenesis. The Y chromosome is distinguished from euchromosome by its characteristics of multiple copies of gene, multiple DNA sequences and high polymorphism. A lot of gene rearrangements occur during its evolution due to the specific gene structure in the Y chromosome. It has been discovered that one subset of such gene rearrangements induces Y-chromosome microdeletions that are involved in male infertility. Spermatogenesis is actually controlled by a network of genes, which may be located on the Y chromosome, euchromosomes or even the X chromosome. Further studies on the genomics and genes in the Y chromosome between sex chromosomes and/or between sex chromosome and euchromosomes will helps us to gain deeper insights into the molecular mechanism of male infertility.