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!
New 3D cultured cells mimic the progress of NASH
02.04.2020 | Tokyo University of Agriculture and Technology
Geneticists are bringing personal medicine closer to recently admixed individuals
02.04.2020 | Estonian Research Council
Published by Marc Tudela, Laura Becerra-Fajardo, Aracelys García-Moreno, Jesus Minguillon and Antoni Ivorra, in Access, the journal of the Institute of Electrical and Electronics Engineers
The project Electronic AXONs: wireless microstimulators based on electronic rectification of epidermically applied currents (eAXON, 2017-2022), funded by a...
The Belle II experiment has been collecting data from physical measurements for about one year. After several years of rebuilding work, both the SuperKEKB electron–positron accelerator and the Belle II detector have been improved compared with their predecessors in order to achieve a 40-fold higher data rate.
Scientists at 12 institutes in Germany are involved in constructing and operating the detector, developing evaluation algorithms, and analyzing the data.
Electrolytes play a key role in many areas: They are crucial for the storage of energy in our body as well as in batteries. In order to release energy, ions - charged atoms - must move in a liquid such as water. Until now the precise mechanism by which they move through the atoms and molecules of the electrolyte has, however, remained largely unknown. Scientists at the Max Planck Institute for Polymer Research have now shown that the electrical resistance of an electrolyte, which is determined by the motion of ions, can be traced back to microscopic vibrations of these dissolved ions.
In chemistry, common table salt is also known as sodium chloride. If this salt is dissolved in water, sodium and chloride atoms dissolve as positively or...
Drops of water falling on or sliding over surfaces may leave behind traces of electrical charge, causing the drops to charge themselves. Scientists at the Max Planck Institute for Polymer Research (MPI-P) in Mainz have now begun a detailed investigation into this phenomenon that accompanies us in every-day life. They developed a method to quantify the charge generation and additionally created a theoretical model to aid understanding. According to the scientists, the observed effect could be a source of generated power and an important building block for understanding frictional electricity.
Water drops sliding over non-conducting surfaces can be found everywhere in our lives: From the dripping of a coffee machine, to a rinse in the shower, to an...
90 million-year-old forest soil provides unexpected evidence for exceptionally warm climate near the South Pole in the Cretaceous
An international team of researchers led by geoscientists from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) have now...
07.04.2020 | Event News
06.04.2020 | Event News
02.04.2020 | Event News
08.04.2020 | Physics and Astronomy
08.04.2020 | Life Sciences
08.04.2020 | Earth Sciences