Radial Hypoplasia, Triphalangeal Thumbs, Hypospadias, And Maxillary Diastema

Schmitt et al. (1982) described a family in which 5 females and 3 males over 3 generations had bilateral, symmetric, nonopposable triphalangeal thumbs and radial hypoplasia. Affected males had first-degree hypospadias and all affected persons had anterior maxillary diastema. No male-to-male transmission was observed; however, transmission to only 2 of 4 daughters by an affected male favors autosomal (as opposed to X-linked) dominant inheritance.