Male fertility issues, reason for most infertility cases in India: CCMB

HYDERABAD: One in every seven couples worldwide is infertile, according to a study conducted by the CSIR-Centre for Cellular and Molecular Biology, with male infertility accounting for 50% of these cases (CCMB).

The problems range from male reproductive system defects to poor sperm quality and hormonal imbalance. Male infertility can be linked to injuries, infections, chronic illness, lifestyle choices, and genetic factors. However, we do not yet know the specifics of how these variables affect fertility.

In order to comprehend the genetic causes of male infertility, Dr. K. Thangaraj's team at the CSIR-Centre for Cellular and Molecular Biology (CCMB), Hyderabad, has been doing research for the past 20 years. Previous studies have shown that 38% of infertile men have certain areas missing from their Y chromosomes, anomalies in those chromosomes, or mutations in their mitochondrial and autosomal genes.

The majority of infertile males are the subjects of their most recent multi-institutional study, which focuses on the causes of infertility in the remaining cases. They have discovered eight new genes in their investigation that were faulty in these Indian men. The study was recently published online in the journal Human Molecular Genetics.

Lead author of the study and ICMR-National Institute for Research in Reproductive and Child Health scientist Dr. Sudhakar Digumarthi, who was a PhD student at CCMB, stated, "We first sequenced all the essential regions of all genes (roughly 30,000 of them) using next-generation sequencing in 47 well-characterized infertile men. The detected genetic alterations were then verified in roughly 1500 infertile men from various parts of India.

"We identified a total of eight genes (BRDT, CETN1, CATSPERD, GMCL1, SPATA6, TSSK4, TSKS, and ZNF318) that were previously unknown for their role in human male fertility," said Dr. Thangaraj, lead investigator of this study and current Director of the DBT-Centre for DNA Fingerprinting and Diagnostics in Hyderabad. He went on to say that they had discovered variations (mutations) in these genes that cause sperm production to be impaired, resulting in male infertility.

The researchers studied a mutation in one of the eight genes, Centrin 1 (CETN1), to understand how it affects sperm production. They studied the effects of CETN1 mutations in cellular models and discovered that the mutation stops cell division, resulting in insufficient sperm production.

"This study should serve as a reminder to society that the majority of all infertility cases are caused by male fertility issues." And a lot of them are brought on by genes inherited from these men's parents, frequently their moms. "It is incorrect to assume that a couple cannot have children solely because of the woman's fertility," Dr. Thangaraj remarked.

According to Dr. Vinay Kumar Nandicoori, Director of the CCMB, the genetic factors identified in this study may serve as potential diagnostic indicators for male infertility, and they may also be used to develop improved management strategies for male infertility, according to Dr. Vinay Kumar Nandicoori.