Department of Anthropology, University of Cincinnati
Thursday All day, Park Concourse
A recent study identified a genetic mutation in the TYRP1 gene that is significantly associated with blond hair color in populations from the Solomon Islands. Although this blondism phenotype is observed across much of Island Melanesia, little is known about the broader distribution of the blondism allele throughout the region, or of its association with hair color in populations outside of the Solomons. Here we report the frequency of this allele in 424 individuals from populations sampled across western Island Melanesia. While the frequency of the blondism allele at this locus (0.20) is slightly lower than, but still consistent with, that reported for the Solomon Island populations further to the east (0.26), this frequency is not uniform across the region. In order to test the hypothesis that this allele is associated with lighter hair and/or skin pigmentation in western Island Melanesia, ANOVA analyses were used to compare mean skin and hair pigmentation levels (measured as the M index) across all three genotype classes. While no significant differences were observed in skin pigmentation, hair M index values differed significantly across groups (F = 3.23, p < 0.05). However, this association may be confounded by the extensive population structure known to characterize this region. We explore methods to control for stratification, as well as examine pigmentation phenotype-genotype associations on individual islands.
Funding provided by the University of Cincinnati.