Microdeletion of Y-chromosome and their high impact on male infertility

Male infertility is a multifactorial genetic disorder. WHO defined infertility as an inability to conceive naturally after at least 1‐year of unprotected intercourse. It is expected that 15% of couples worldwide who seeks children have infertility while male factor alone contributes about 50% in childless couples. In more than half of infertile male are unknown idiopathic causes. Semen analysis shows abnormal conditions such as azoospermia, oligozoospermia, teratozoospermia, asthenozoospermia, necrospermia, and pyospermia.[1‐6] The prevalence of primary and secondary infertility varies between 29% and 71%, but about 30% of cases of reduced infertility are still unknown. The Y‐chromosomes play a significant role in maintaining fertility in human. Hence, it is essential to understand the molecular structure of Y‐chromosome and their regions associated with infertility. Y‐Chromosome is one of the smallest chromosomes. It consists of euchromatic, heterochromatic regions, and covered 95% by male‐specific region. There are 60 million nucleotides including 156 transcription units, 78 protein‐coding genes, and 27 distinct proteins as shown in Figure 1.