rs1805009, known as Asp294His or D294H and located in the MC1R gene, is the most common variant associated with red hair (redheads) and poor tanning ability in one study. [PMID 7581459]
The risk allele is rs1805009(C), compared with the wild-type rs1805009(G) allele.
See also OMIM 155555.0001
blog about designing melanocortin analogs specific to these genotypes.
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