- rs1805009, known as Asp294His or D294H; the most common variant associated with red hair and poor tanning ability in one study [PMID 7581459]
- rs1805007, known as Arg151Cys or R151C; associated with red hair, and in redheaded females, linked to being more responsive to the anesthetics pentazocine, nalbuphine, and butorphanol, often used by dentists [PMID 9571181, PMID 12663858]
- rs1805008, known as Arg160Trp or R160W; associated with red hair in an Irish population [PMID 9665397]
23andMe blog Red Hair snps
gs238 looks for redheads
blog about designing melanocortin analogs specific to these genotypes.
Anaesthesiology study finds that "anaesthetic requirement is increased in redheads".
prevalence of the gene in worldwide groups.
myths of red hair genetics