Editing Human skin color (section)

=== Dark skin ===
{{Main|Dark skin}}
All modern humans share a [[Mitochondrial Eve|common ancestor]] who lived around 200,000 years ago in Africa.<ref name="Soares P, Ermini L, Thomson N, et al. 2009 740–59">{{cite journal |title=Correcting for purifying selection: an improved human mitochondrial molecular clock |journal=Am. J. Hum. Genet. |volume=84 |issue=6 |pages=740–59 |date=June 2009 |pmid=19500773 |pmc=2694979 |doi=10.1016/j.ajhg.2009.05.001 |last1=Soares |first1=P |last2=Ermini |first2=L |last3=Thomson |first3=N |last4=Mormina |first4=M |last5=Rito |first5=T |last6=Röhl |first6=A |last7=Salas |first7=A |last8=Oppenheimer |first8=S |last9=MacAulay |first9=V |last10=Richards |first10=M. B.}}</ref> Comparisons between known skin pigmentation genes in [[Common chimpanzee|chimpanzees]] and modern Africans show that dark skin evolved along with the loss of body hair about 1.2 million years ago and that this common ancestor had dark skin.<ref name=Rogers2004b>{{cite journal |title=Genetic Variation at the MC1R Locus and the Time since Loss of Human Body Hair |journal=Current Anthropology |volume=45 |issue=6 |pages=105–108 |year=2004b |doi=10.1086/381006 |jstor=381006|last1=Rogers |first1=Alan R. |last2=Iltis |first2=David |last3=Wooding |first3=Stephen|s2cid=224795768 }}</ref> Investigations into dark-skinned populations in South Asia and Melanesia indicate that skin pigmentation in these populations is due to the preservation of this ancestral state and not due to new variations on a previously lightened population.<ref name=Harding2000>{{cite journal |last1=Harding |first1=R |last2=Healy |first2=E |last3=Ray |first3=A |last4=Ellis |first4=N |last5=Flanagan |first5=N |last6=Todd |first6=C |last7=Dixon |first7=C |last8=Sajantila |first8=A |last9=Jackson |first9=I |last10=Birch-Machin |first10=Mark A. |last11=Rees |first11=Jonathan L. |title=Evidence for Variable Selective Pressures at MC1R |journal=The American Journal of Human Genetics |volume=66 |pages=1351–61 |year=2000 |doi=10.1086/302863 |pmid=10733465 |issue=4 |pmc=1288200}}</ref>

==== MC1R ====
[[File:MC1R (rs885479).png|thumb|MC1R (rs885479)]]
The [[melanocortin 1 receptor]] (MC1R) gene is primarily responsible for determining whether pheomelanin and eumelanin are produced in the human body. Research shows at least 10 differences in MC1R between African and chimpanzee samples and that the gene has probably undergone a strong [[Directional selection|positive selection]] (a [[selective sweep]]) in early Hominins around 1.2 million years ago.<ref>{{cite journal|title=Genetic variation at the MC1R locus and the time since loss of human body hair|journal=Current Anthropology|year=2004a|volume=45|issue=1|pages=105–124|doi=10.1086/381006|last1=Rogers|first1=Alan R.|last2=Iltis|first2=David|last3=Wooding|first3=Stephen|s2cid=224795768 }}</ref> This is consistent with positive selection for the high-eumelanin [[phenotype]] seen in Africa and other environments with high UV exposure.<ref name=Rogers2004b/><ref name=Harding2000/>