[Variations in expressivity and penetrance of hypodontia].

The intensity of expressivity and penetrance of anomalies through generations can be established by means of genealogical analysis. In the present study thirty five family pedigrees, including three generation family members, have been analysed. Variable expressivity of hypodontia has been established in 48.57% families. Pedigrees of 21 families showed the autosomal dominant mode of inheritance. Three families expressed hypodontia only in one (third) generation. In 12 families hypodontia has been established only in the proband what was compatible with the polygenic inheritance. In 12 (34.28%) families hypodontia showed penetrance through two generations, and in 9 (25.71%) families penetrance has been observed through three generations.