A hormone called progesterone is important for preparing the uterine lining for egg implantation and in maintaining the early stages of pregnancy. Almost one in three women with European descent inherited a genetic variant of the progesterone receptor called V660L from Neanderthals. According to a new study, its carriers have higher fertility, more siblings, fewer miscarriages, and less bleeding during early pregnancy.
Source: Sci News
Progesterone is a steroid sex hormone produced by the ovaries, placenta, and adrenal glands that is involved in pregnancy, menstrual cycle, libido and embryogenesis in placental mammals.
The progesterone receptor is encoded by the PGR gene on chromosome 11, and is most highly expressed in the endometrium.
“The progesterone receptor is an example of how favorable genetic variants that were introduced into modern humans by mixing with Neanderthals can have effects in people living today,” said study first author Dr. Hugo Zeberg, a researcher in the Department of Neuroscience at Karolinska Institutet and the Max Planck Institute for Evolutionary Anthropology.
In the study, Dr. Zeberg and colleagues analyzed data from the UK Biobank cohort involving 452,264 Britons with European descent.
They found that almost one in three women inherited the V660L variant from Neanderthals.
Allele frequency of V660L in 26 populations: the African American populations (ASW: African Ancestry in Southwest US, ACB: African Caribbeans in Barbados) have a lower frequency of V660L, similar to that in African populations, whereas North Americans with European ancestry (e.g., CEU: Utah Residents with Northern and Western European Ancestry) have frequency similar to European populations. Image credit: Zeberg et al, doi: 10.1093/molbev/msaa119.
“The proportion of women who inherited this gene is about 10 times greater than for most Neanderthal gene variants,” Dr. Zeberg said.
“These findings suggest that the Neanderthal variant of the receptor has a favorable effect on fertility.”
“Our study shows that women who carry the Neanderthal variant of the receptor tend to have fewer bleedings during early pregnancy, fewer miscarriages, and give birth to more children,” the researchers said.
“Molecular analyses revealed that these women produce more progesterone receptors in their cells, which may lead to increased sensitivity to progesterone and protection against early miscarriages and bleeding.”
The findings were published in the journal Molecular Biology and Evolution.
Source: Sci News