A new research study has revealed that natural selection is driving a surge in redheads.
A team of researchers from Harvard University assessed ancient DNA from nearly 16,000 people across more than 10,000 years in West Eurasia, including the Middle East, the Caucasus, Europe, and parts of Central Asia and North Africa.
The study found that certain genes became much more common because they likely offered some kind of advantage or were influenced by the changing environment.
As per researchers’ findings, genes related to red hair, lighter skin tones, and coeliac disease are becoming more common.
“Perhaps having red hair was beneficial 4,000 years ago, or perhaps it came along for the ride with a more important trait,” the study, published in the scientific journal Nature, suggested.
The findings also suggest that natural selection has played a much larger role in shaping the modern human genome than previously understood.
The study also doubles the existing library of ancient human DNA, adding 10,016 new ancient DNA sequences and bringing the total dataset to over 22,000 individuals.
“With these new techniques and a large amount of ancient genomic data, we can now watch how selection shaped biology in real time. Instead of searching for the scars natural selection leaves in present-day genomes using simple models and assumptions, we can let the data speak for itself,” Author of the study, Ali Akbari, senior staff scientist in the lab of Harvard geneticist David Reich, said.
Moreover, Natural selection appears to have increased the prevalence of variants linked to coeliac disease and Crohn’s disease.
Evolution has also favoured traits that offer resistance to leprosy and HIV, including the lower risk of bipolar disorder, alcoholism, and schizophrenia.
The study also suggested that lower BMI, waist-to-hip ratio, and lower body fat are also linked to DNA changes.
As per researchers, the study findings can also help scientists identify new genetic factors in health and diseases, leading to revolutionary changes in medical sciences.
