Gene mutation causes infertility in 2-6% of 10.8 million infertile men: study

“The absence of vas deference in males is due to this mutation remains largely undiagnosed by doctors. If IVF procedure is allowed for such men, the gene mutation may pass on to their offspring making their male child also infertile. The research shows it is important to counsel couples suffering from this congenital defect,” said principal investigator at NIRRH, Dr Rahul Gajbhiye.

The research, conducted from 2011 to 2016, was published in the May edition of the Indian Journal of Medical Research. As part of the study, 76 infertile men from across the country, who suffered from this defect, were studied. It was observed that congenital absence of vas deference was present in 95 per cent of the men who had cystic fibrosis.

Andrologist and co-author Dr Vijay Kulkarni said when couples fail to conceive and approach infertility experts, this congenital disorder was rarely diagnosed. “The CFTR gene mutation can manifest in lungs, pancreas or other organs. In India, it was assumed that the mutation did not affect vas deference until our research proved otherwise,” he said.
The research revealed that the prevalence of the gene mutation that causes infertility was higher in India than Italy, Iran, Argentina, Germany, Taiwan or France. But India had lower incidence than Egypt and China in CFTR mutation causing absence of vas deference.

In March, a 35-year-old man was referred to Kulkarni by a Mumbai-based gynaecologist. “The man’s semen samples were taken and it had only 0.5 cc sperms. This is negligible,” he said.

On examination, Kulkarni found that the man had no vas deference. “Counselling by geneticist was required to make the couple understand that if they undergo ART, the embryo will have to be diagnosed for CFTR mutation. This counselling happens regularly in the West. In India, only a few specialised IVF clinics look into this gene mutation,” Kulkarni said. The andrologist receives two to three such cases every month, which are referred by various infertility experts in Mumbai.

Another andrologist Dr Rupin Shah, who consults at Lilavati hospital, said there is no known cause for this hereditary gene mutation. The research also found that in 11-20 per cent of such infertile patients, there was only one kidney since birth.