Chinese scientists solve the mystery of lighter complexion in East Asian populations

A recent joint study by Kunming Institute of Zoology of Chinese Academy, Sciences and several other research institutes has solved the mystery of lighter complexion of East Asian populations. Scientists discovered the OCA2 gene, a pigment gene that shows the biggest genetic difference between the light-skinned Chinese Han population and the dark-skinned Austro-Asiatic population. An amino acid mutation in the gene can significantly affect melanin synthesis and maturation, resulting in the lighter complexion in East Asian populations.

East Asia has a great span of latitudes, with the annual amount of ultraviolet exposure varying at different latitudes. In order to understand the genetic mechanism of colour adaptation in East Asian populations, the Kunming-based Laboratory of Genetic Resources and Evolution headed by Dr. Su Bing, along with the Houston-based Baylor College of Medicine, Tsinghua University and Liaoning Normal University gathered nearly 1,000 blood samples and skin colour phenotype samples from members of East Asian populations. Through whole genome microarray analyses, they found OCA2, the pigment gene that shows the biggest genetic difference between the light-skinned Chinese Han population and the dark-skinned Austro-Asiatic population. Further molecular evolution analyses revealed that OCA2 is subject to strong positive Darwinian selection in East Asia populations, so that an amino acid mutation is commonly seen in East Asian populations while not in European and African populations. Through skin colour phenotype correlation analysis, melanoma cell function experiments, zebrafish transgenic experiments, mice Cas9 genetic mutation locus replacement experiments and TEM analysis, it is proven that the mutation can significantly affect melanin synthesis and maturation, resulting in the lighter complexions in East Asian population.

The study has uncovered the molecular mechanism underlying the lighter complexion in East Asian populations, which is of great significance for a deeper understanding of the genetic mechanisms of convergent evolution and phenotypic adaptive evolution. The findings were recently published in the internationally renowned journal Molecular Biology and Evolution.

Chinese scientists solve the mystery of lighter complexion in East Asian populations

A recent joint study by Kunming Institute of Zoology of Chinese Academy, Sciences and several other research institutes has solved the mystery of lighter complexion of East Asian populations. Scientists discovered the OCA2 gene, a pigment gene that shows the biggest genetic difference between the light-skinned Chinese Han population and the dark-skinned Austro-Asiatic population. An amino acid mutation in the gene can significantly affect melanin synthesis and maturation, resulting in the lighter complexion in East Asian populations. East Asia has a great span of latitudes, with the annual amount of ultraviolet exposure varying at different latitudes. In order to understand the genetic mechanism of colour adaptation in East Asian populations, the Kunming-based Laboratory of Genetic Resources and Evolution headed by Dr. Su Bing, along with the Houston-based Baylor College of Medicine, Tsinghua University and Liaoning Normal University gathered nearly 1,000 blood samples and skin colour phenotype samples from members of East Asian populations. Through whole genome microarray analyses, they found OCA2, the pigment gene that shows the biggest genetic difference between the light-skinned Chinese Han population and the dark-skinned Austro-Asiatic population. Further molecular evolution analyses revealed that OCA2 is subject to strong positive Darwinian selection in East Asia populations, so that an amino acid mutation is commonly seen in East Asian populations while not in European and African populations. Through skin colour phenotype correlation analysis, melanoma cell function experiments, zebrafish transgenic experiments, mice Cas9 genetic mutation locus replacement experiments and TEM analysis, it is proven that the mutation can significantly affect melanin synthesis and maturation, resulting in the lighter complexions in East Asian population. The study has uncovered the molecular mechanism underlying the lighter complexion in East Asian populations, which is of great significance for a deeper understanding of the genetic mechanisms of convergent evolution and phenotypic adaptive evolution. The findings were recently published in the internationally renowned journal Molecular Biology and Evolution.