Progress in the genetic studies of spermatogenesis abnormalities.

About 15% couples suffer from infertility, half of which are caused by male factors. Male infertility usually manifests as teratozoospermia, oligospermia and/or asthenospermia, of which the most severe form is azoospermia. In this review, we summarize the recent progress in the study of genetic factors involved in nonobstructive azoospermia and teratozoospermia, Recently, with the rapid development of high-throughput chips and sequencing technologies, many genetic factors of spermatogenesis have been discovered and analyzed. For the nonobstructive azoospermia, genome-wide association studies (GWAS) and high-throughput sequencing revealed many risk loci of nonobstructive azoospermia. For the teratozoospermia, the application of whole-exome sequencing (WES) revealed a series of disease-causing genes, greatly enriching our knowledge of teratozoospermia including multiple morphological abnormalities of the flagella (MMAF). The discovery of lots of disease genes helped the characterization of the pathological mechanisms of male infertility. Therefore, a comprehensive and in-depth understanding of genetic factors in spermatogenesis abnormalities will play important roles in the clinical diagnosis, treatment and genetic counseling of male infertility.