8 novel genes cause of male infertility in India: Study

Eight novel genes in Indian men have been identified by CSIR- Centre for Cellular and Molecular Biology (CCMB), Hyderabad as the core reason for male infertility.

Male infertility is when there are defects in the male reproduction system in terms of sperm count, deficiencies in semen quality, hormonal imbalance, injuries, infections, chronic illness, lifestyle choices and genetic factors.

Genes are known to play a role and scientists in their research study found that Y chromosomes had abnormalities, mutations in their cell and autosomal genes. It has been noted in earlier studies on male infertility, 38 percent of them had specific regions missing in their Y chromosomes.

The multi-institutional study focused on infertility in rest of the cases and it was found that there are 8 novel genes responsible for male infertility. These 8 genes are (BRDT, CETN1, CATSPERD, GMCL1, SPATA6, TSSK4, TSKS and ZNF318)

Dr K Thangaraj, lead investigator of the study and Director of the DBT-Centre for DNA Fingerprinting and Diagnostics, Hyderabad says, "These eight genes were not known earlier and it is now showing that mutations in these genes is leading to impaired sperm production."

Dr Sudhakar Digumarthi, lead author of the study, who was a PhD student of CCMB and presently scientist at ICMR-National Institute for Research in Reproductive and Child Health in Mumbai, said, "We first sequenced all the essential regions of all genes (around 30,000 of them) using next generation sequencing in 47 well-characterized infertile men. We then validated the identified genetic changes in about 1500 infertile men from different parts of India."

The researchers found that mutation arrests cell division leading to insufficient sperm production.

"This study should be a reminder to the society that half of the infertility cases are due to problems in men. And many of them are due to genes that come from the parents, often mothers, of these men. It is wrong to assume a couple cannot bear children because of only the woman's fertility," remarked Dr Thangaraj.

Dr Vinay Kumar Nandicoori, Director, CCMB said, "The genetic causes established in this study could be used as potential diagnostic markers for male infertility, and development of improved management strategies for male infertility".

The study is published in the journal Human Molecular Genetics.