Discover Two New Genes That May Explain Morning Sickness

Understanding Morning Sickness in Pregnant Women

Prevalence and Impact

Morning sickness is a prevalent condition among pregnant women, with various underlying reasons contributing to its occurrence. Research indicates that up to 18% of women resort to medication to alleviate nausea. Despite its widespread nature, the exact cause of morning sickness remains unknown. Without proper treatment, this condition can escalate, leading to symptoms such as vomiting, dehydration, weight loss, and nutritional deficiencies. In severe cases, it may even result in preterm birth and birth defects.

Genetic Insights into Morning Sickness

In a study published in *Nature Communications*, researchers led by Fejzo explored the genetic factors associated with morning sickness. Utilizing genetic data from female participants of 23andMe, the study focused on women of European ancestry, including 1,306 individuals who experienced and sought treatment for morning sickness, along with 15,756 who reported no symptoms.

The research involved a genome-wide association study aimed at identifying specific gene variants linked to the occurrence of morning sickness. The findings revealed two genomic locations potentially associated with this condition. One location included the genes GDF15 and LRRC25, with additional genes implicated in activating GDF15 also linked to morning sickness.

Role of Key Genes

GDF15 encodes a protein that is activated in the placenta and increases in concentration throughout pregnancy. This protein is crucial for reducing inflammation, promoting placenta development, and ensuring the pregnancy progresses to full term. Additionally, GDF15 is involved in regulating appetite and weight gain during pregnancy. The second gene identified, IGFBP7, also contributes to the growth and maintenance of the placenta.

Future Research Directions

Looking ahead, further genome association studies are necessary to investigate the relationship between the identified genes and morning sickness in women of non-European ancestry. Future research should also aim to clarify the specific roles of GDF15 and IGFBP7 in the management of morning sickness. A deeper understanding of these genes and their functions will enhance our comprehension of why morning sickness occurs in otherwise healthy women and may identify potential treatment targets.

Reference

Fejzo, M.S., Sazonova, O.V., Sathirapongsasuti, J.F. et al. Placenta and appetite genes GDF15 and IGFBP7 are associated with hyperemesis gravidarum. Nat Commun 9, 1178 (2018). https://doi.org/10.1038/s41467-018-03258-0