Scientists from the Center for Cellular and Molecular Biology (CCMB) have identified the genes responsible for male fertility. If deleted or damaged, they cause sterility and also lead to the failure of assisted reproduction techniques.
The discovery could help many men who are unable to have children. In some cases, it could save them as expensive as useless fertilization cycles. It is estimated that around 1 in 7 couples worldwide have fertility problems. In about 50% of cases, the cause is of the male partner.
The factors that lead to infertility can be many: total lack of spermatozoa; sperm deficiency or lack of motility; spermatozoa with an abnormal shape. In some cases, changing lifestyle is enough to increase fertility levels. In many others, genetic factors play an essential role and assisted reproduction remains the only solution. The authors of the study analyzed some genes present in the Y chromosome, responsible for sperm production.
When these genes are missing, fertility collapses in an unrecoverable manner. According to the researchers, this would be the cause of about 8.5% of cases of male infertility. In the worst cases, subjects with this type of genetic variants do not even benefit from assisted fertilization. To identify the variants, the team analyzed the DNA of 973 infertile men. They compared it to that of 587 fertile men. This allowed them to identify a combination of variants typical of the Indian population.