Scientists at the University of Southern California have found nine new genes that are linked to hyperemesis gravidarum (HG). HG is the most serious kind of pregnancy sickness.
A Tough Condition
About 2 % of pregnant women get HG. It causes strong nausea and vomiting that make it hard to eat or drink. In the worst cases, a mother can become very weak and the baby can be at risk.
Key Gene Findings
Earlier work showed that a gene called GDF15 is important for pregnancy nausea. The new study adds six more genes that had never been linked to HG before. Together, ten genes are now known to affect the condition.
How the Study Was Done
The researchers looked at the DNA of 10,974 women who had HG and compared it with 461,461 women who did not. The group included people of European, Asian, African and Latino backgrounds. They used a method called a genome‑wide association study (GWAS) to spot differences.
What the New Genes Do
The new genes are involved in things like appetite, hormone control, metabolism and how the brain learns. One of them, TCF7L2, is also a strong risk factor for type 2 diabetes and may affect a hormone that controls blood sugar and nausea.
Other genes may help explain why some women develop strong food aversions during pregnancy.
Possible New Treatments
Current medicines help only about half of the women with HG. The new gene clues could point to fresh drug targets. Researchers are also starting a trial with metformin, a diabetes drug that raises GDF15 levels, to see if it can lower nausea before pregnancy.
Future Steps
With more than double the number of known HG genes, scientists can explore the biology of the condition more deeply. This could lead to personalized treatments based on a woman’s genetic profile.