Researchers from the University of Michigan have unveiled a genetic variant that influences the ratio of sexes in newborn children. The findings of their study were recently published in the scientific journal Proceedings of the Royal Society B: Biological Sciences.
Professor Jiangi Zhang, an expert in ecology, evolutionary biology, and evolutionary genetics at the University of Michigan, along with graduate student Silyan Sona, conducted an analysis of a large-scale database from the UK Biobank, which contains genetic information from 500,000 British participants. Through their research, they identified a rare nucleotide change, known as RS144724107, that increases the likelihood of having a girl by 10%. This mutation is present in only 0.5% of the study participants.
The newly discovered genetic variant is situated near the adamts14 gene, which is part of the adamts family involved in spermatogenesis and fertilization processes. Additionally, two other genes, RLF and KIF20B, were identified by the scientists as potentially impacting sex ratio. However, further confirmation in other samples is necessary to validate these results.
The study’s results align with Fisher’s principle in evolutionary biology, named after the renowned British statistician and geneticist Ronald Fisher. The principle suggests that natural selection favors genetic variations that enhance the birth rate of the less common sex in a population. This discovery could have practical implications in animal husbandry, particularly in species where a specific sex holds significant economic importance, such as chickens for egg production and cows for milk production. Identifying genetic variants with effects similar to the RS144724107 mutation in agricultural animals could lead to substantial profits and improvements in animal welfare.
Currently, the researchers are planning to replicate their findings in other samples, although this task presents challenges due to the requirement for a sizable sample size and the rarity of the genetic variant they uncovered.