The study, published in Nature Genetics, is the first comprehensive view of the relationships between genes and infertility. The results may lead to improved diagnosis and treatments for fertility-related conditions.
Infertility, defined as the inability to achieve pregnancy within 12 months of regular unprotected sexual intercourse, is thought to affect one in six couples around the world. It is associated with a wide range of social, environmental, and genetic factors but the exact cause is not known for up to 28% of couples and 40% of women.
Previous studies have suggested that infertility may be caused by problems with reproductive hormones and obesity but so far there has been limited evidence on how our genes affect fertility.
Key findings:
- 25 genetic variants for infertility were identified, 22 in women and three in men;
- 269 genetic variants were found to be associated with hormones that can affect fertility, including follicle-stimulating hormone (which has different functions depending on sex and age), luteinising hormone (which triggers ovulation in women and sperm production in men), oestradiol (the main oestrogen found in women), and testosterone. However, no genetic association was found between female infertility and reproductive hormones;
- Three genetic variants were found to be associated with male infertility. One of the three variations is near ENO4, a gene linked to sperm movement. When this gene is removed in male mice, it causes infertility.
Read the full story on the Nuffield Department of Population Health website.