Extent of Sex Influence on Carabelli's Polymorphism

Abstract

Population investigation of sex differences in the degree of expression of Carabelli''s trait of the human tooth showed no statistically significant dimorphism ([chi]2 = 3.9 for 2 df). Sexual dimorphism is probably notpresentin the manifestation of Carabelli''s trait. Reference to this polymorphism may be made without correction for sex in population studies. Comparing brother-brother, sister-sister and brother-sister sibling pairs for concordance with respect to degree of Carabelli''s trait, brothers showed more similarity than sisters. Evidence of a sex influence operating within sibships may possibly be an example of a heterozygote effect involving the sex chromosomes.