Two pedigrees from Kerala and data on 274 families from 4 slates in India have been reported here along with some population data on tongue pigmentation. Analysis of the pedigrees and sibships reported here and previously, revealed that neither an autosomal dominant, nor a sex-linked, a sex-limited, or a non-genetic chance hypothesis could interpret the data. Tests for segregations in the families support the genetic hypothesis that tongue pigmentation is an autosomal recessive character in human populations governed by 2 allelic genes, the ‘normal’ allele (A) being dominant over the ‘pigmented’ allele (a). There are certain indications which suggest occasional failures of penetrance of the tongue pigmentation allele.
- Genetic study
- Tongue pigmentation