Sort of and possible. I’ve been talking about this for years, and Greg Cochran points me to an abstract at the human genetics conference referenced earlier. Novel coding variation at TYRP1 explains a large proportion of variance in the hair colour of Solomon Islanders:

The Solomon archipelago comprises over 1,000 islands located east of Papua New Guinea and has a population noted for wide variation in hair pigmentation. 1200 samples were collected from 16 centres and hair colour measured in donors by spectrophotometer. Analysis of 589,241 single nucleotide polymorphisms across a subset of 42 dark haired and 43 blond haired individuals revealed a signal for pigmentation driven by 27 markers on 9p23 at the TYRP1 gene (rs13289810…). There were no systematic differences in ancestry between dark and blond haired participants indicating that this variation is unlikely to be due to recent introgression from other populations. Sequencing of TRYP1 showed complete conservation of this locus bar nucleotide 5,888(NG_011750), which was homozygous C in dark haired individuals and T in blonds. The resulting CGC->TGC missense mutation changes the 93 amino acid in exon 2 from an Arginine to a Cystine. Genotyping of TYRP1(93C/T) in all samples and analysis showed that in ...