Growth
of
thick hair on the pinnae of the
external ears of males has long been presented in genetics
textbooks as a Y-linked trait,
common in some Indian populations. Recent molecular studies (Lee et
al. 2004) indicate that Indian
men with hairy ears do not share common Y-chromosome DNA sequences, and that the
frequenices of the Y-chromosome
haplotypes found among men with hairy
ears are no different than in a control group of men with non-hairy
ears. The data thus indicate
that hairy-eared men are unrelated and do not share a common Y-linked
allele. The trait may instead be a sex-limited
trait (like beard growth) influenced by one or more autosomal
loci.
