Gene discovered that makes it easier to have a baby girl

A large new analysis finds that some people carry a gene variant that makes them more likely to have daughters than sons .

In the new study, researchers analyzed the genomes of about 450,000 men and women with data in the UK Biobank.

They found that the gene variant rs144724107 increases a person's chance of having a daughter by 10% . This means that in a given pregnancy, a person with that gene has a 60% chance of having a daughter instead of the expected 50/50 chance.

The researchers are still unclear whether the mother, father, or both need to carry the gene to affect the odds of having a daughter.

The gene variant rs144724107 may make a person more likely to have a daughter - (Photo: iStockphoto).

The team also doesn't know exactly how the rs144724107 gene variant increases the likelihood of having a girl. However, they do know that in DNA molecules, rs144724107 is located near a member of the ADAMTS gene family – a family of genes involved in sperm production and fertilization. This makes it possible for rs144724107 to influence gender by influencing how this gene is turned on/off .

According to LiveScience on October 24, this discovery could strengthen Fisher's principle, which argues that most of the time, sexually reproducing organisms will produce equal numbers of males and females.

According to Professor Jianzhi Zhang, working at the University of Michigan (USA), this means that if there are more males than females in a population, evolutionary pressure will favor gene variants that increase the number of females to balance the sex ratio. The same will happen in the opposite direction if there are more females than males.

To prove Fisher's principle, researchers need to identify gene variants that influence an individual's ability to produce male or female offspring. Such variants are difficult to detect in humans, in part because humans have few children.

However, thanks to the large-scale data system of UK Biobank, the team identified the variant rs144724107 and found it was present in only 0.5% of the 450,000 people analyzed. At the same time, the team believes that there are other variants that also have an impact on the ability to have boys or girls.

The team's findings will need to be confirmed in other groups of people in other countries. In addition, the team will need to see if similar variants exist in the genomes of more diverse populations, as the study only included people of European ancestry.

The study was published in the journal Proceedings of the Royal Society B: Biological Sciences .