The proclivity of Spaniards to bask in regions like the Costa del Sol while their northern European counterparts must stay under cover to protect their paler skin or risk skin cancer is due in large part to the pigment producing qualities of the MC1R gene locus. The MC1R gene, expressed in skin and hair follicle cells, is more diverse in Eurasian populations compared to African populations.
Now, a team of researchers led by Santos Alonso, et. al., have examined the evolutionary selective pressure for MC1R among a large population of Spaniards in comparison to their Northern Europeans counterparts as well as individuals with melanoma. Using data from the 1,000 Genomes Project as well as samples from different regions of Spain, they authors show that selection for the MC1R locus is strong in South Europeans, but not the case for Northern Europeans.
Two evolutionary selective processes seem to be acting on MC1R in Southern Europeans. On the one hand, there is selective pressure to maintain at high frequencies the ancestral form of the gene, also the one most common in Africans. But simultaneously, one gene variant seems to be favored in South Europeans. This gene variant, called the V60L allele, has been associated before with red/blond hair and fair skin.
World frequency distribution of V60L is confined mostly to Europe and the Near East but mostly absent in East Asia and Africa, indicating that the first appearance of V60L mutation occurred some time after modern humans left Africa but before dispersal throughout Europe. Fair skin depigmentation could be a useful change for the adaptation of humans to this new environment. Traditionally, depigmentation had been hypothetically explained as a function of the need of humans to synthesize vitamin D in areas of reduced sun light (compared to Africa). "We have not proved that this is the underlying reason for the signature of positive selection on V60L, but our data adds support to this view, although this point needs to be further explored" says Santos Alonso, senior author of the paper.
Interestingly, the same allele V60L has been associated to increased risk of melanoma, the most dangerous of skin cancers. This indicates", says Saioa López, one of the two main authors of the paper, "that the increase in fitness for the population as a consequence of depigmentation has had a collateral damage consequence for the individual´s health. This can be reconciled if we assume that melanoma is typically a post-reproductive disease, and consequently should have little effect on the individual's genetic contribution to the next generation. It constitutes a kind of evolutionary 'buy now pay later' trade-off.'"
To access the advanced online edition of the article, go to: http://mbe.oxfordjournals.org/content/early/recent
Joe Caspermeyer | EurekAlert!
Preventing metastasis by stopping cancer cells from making fat
23.01.2020 | Université catholique de Louvain
Possible Alzheimer's breakthrough suggested
22.01.2020 | Case Western Reserve University
Researchers from Dresden and Osaka present the first fully integrated flexible electronics made of magnetic sensors and organic circuits which opens the path towards the development of electronic skin.
Human skin is a fascinating and multifunctional organ with unique properties originating from its flexible and compliant nature. It allows for interfacing with...
Researchers of the Carl Gustav Carus University Hospital Dresden at the National Center for Tumor Diseases Dresden (NCT/UCC), together with an international...
A Duke University research team has identified a new function of a gene called huntingtin, a mutation of which underlies the progressive neurodegenerative...
For years, a new synthesis method has been developed at TU Wien (Vienna) to unlock the secrets of "strange metals". Now a breakthrough has been achieved. The results have been published in "Science".
Superconductors allow electrical current to flow without any resistance - but only below a certain critical temperature. Many materials have to be cooled down...
KIT researchers develop novel composites of DNA, silica particles, and carbon nanotubes -- Properties can be tailored to various applications
Using DNA, smallest silica particles, and carbon nanotubes, researchers of Karlsruhe Institute of Technology (KIT) developed novel programmable materials....
16.01.2020 | Event News
15.01.2020 | Event News
07.01.2020 | Event News
23.01.2020 | Physics and Astronomy
23.01.2020 | Information Technology
23.01.2020 | Trade Fair News