Evidence for the association of Y-chromosome haplogroups with susceptibility to spermatogenic failure in a Chinese Han population

Introduction: Y-chromosomes are genetically highly variable due to frequent structural rearrangements. The variations may create a genetic background for the susceptibility to Y related spermatogenic impairment, although few data have been accumulated about the possible correlation between the Y chromosome haplotype and the predisposition of males to the spermatogenic failure. Materials and Methods: To investigate the possible association of Y chromosome background with spermatogenic failure, we compared the distribution of 18 Y chromosome haplogroups between 414 infertile men with azoo/oligozoosperma and 262 normozoospermic men with or without AZFc deletions in a Han population of Southwest China. Results: A significant population difference in Y haplogroup distribution was observed between the groups of normozoospermia and azoo/oligozoosperma, and between the patient groups of oligozoospermia and azoospermia without AZFc deletions. Inter-population comparison of Y haplogroup frequencies showed that the distribution of haplogroups C, K*and O3* were significantly different between the groups. Conclusion: The present study provides evidence for the association of Y chromosome background with impaired spermatogenesis, suggesting that Y variations play a role in the occurrence and even the severity of spermatogenic failure. Furthermore, not only AZFc deletions, but also other Y chromosome structural variations may be important for determining the susceptibility to spermatogenic failure. Our findings emphasize the necessity of more extensive study on the Y variations for better understanding the spermatogenesis and its pathology.