An analysis of human DNA suggests female populations have been larger than male populations throughout history.
Researchers used a new technique that allowed them to obtain higher quality paternal genetic information to look at past demographics across the globe, BioMed Central reported.
To make their findings the researchers compared paternally inherited Y chromosomes (NRY) with the maternally inherited mitochondrial DNA (mtDNA) of 623 males from 51 populations. The results suggest female populations were superior in size before the out-of-Africa migration and remained so in future generations.
The phenomenon may be a partial result of polygyny, in which one male mates with multiple females. Another factor in the disparity between male and female populations is the fact that females tend to move to live with their husbands, allowing females to make a more significant genetic contribution to the global gene pool.
To make their findings researchers from the Max Planck Institute for Evolutionary Anthropology developed a high-resolution Y chromosome sequencing assay that gave them the chance to look at genetics like never before. The new method allowed them to get an equal look at both maternal and paternal genetic histories and make a comparison.
The study's results confirmed past findings suggesting there are larger differences in paternal NRY than in mtDNA, but these differences are not as dramatic as was previously believed.
In the future the researchers hope to use this groundbreaking analysis technique to look deeper into maternal and paternal influences on global populations.
"Our new sequencing technique removes previous biases, giving us a richer source of information about our genetic history. It allows us to take a closer look at the regional differences in populations, providing insights into the impact of sex-biased processes on human genetic variation," said Mark Stoneking, Department of Evolutionary Genetics, Max Planck Institute and an author on the paper.
The findings were published Sept. 24 in the journal Investigative Genetics.
