A genetic analysis of clubfoot in Hawaii.

The roles of major genes and multifactorial inheritance in the etiology of clubfoot (talipes equinovarus) were investigated based on 365 nuclear families consisting of three major racial groups of Hawaiians, Caucasians, and Orientals in Hawaii. Complex segregation analysis was employed using the mixed model with four parameters: major gene displacement (t), degree of dominance (d), gene frequency (q), and heritability (H). Heterogeneity was evident among the racial groups in the pattern of segregation of clubfoot. The most plausible genetic model is the presence of major gene effects with the multifactorial component for the Hawaiian and Caucasian groups, whereas no major gene action is evident for the Oriental group.