Y chromosome infertility is a common genetic condition that affects male fertility, occurring in approximately 1 in 2,000 to 1 in 3,000 males of all ethnic groups. It accounts for about 13 percent of azoospermia (absence of motile sperm in semen) and 5 percent of severe oligospermia (low  sperm count) cases. Y-chromosome microdeletions, a specific type of genetic mutation, are known to cause this condition.