The Summitt syndrome: observations on a third case.

A 6 1/2 year old male presented with acrocephaly, brachydactyly, clinodactyly, mild syndactyly of the hands and feet, genu valgum, and marked obesity. Roentgenograms of the hands revealed hypoplasia or aplasia of the middle phalanges. Roentgenograms of the feet revealed hypoplasia of the middle phalanges and deformity of the proximal phalangeal epiphyses of the great toes. Chromosomes studies revealed a normal 46,XY karyotype, and psychological testing revealed low normal intelligence. Current data support autosomal recessive inheritance, although X-linkage cannot be excluded.