Congenital contractural arachnodactyly in two double second cousins: possible homozygosity.

A Bedouin family with two girls affected by severe congenital contractural arachnodactyly (CCA) is described. The girls were double second cousins. One of the girls also had ambiguous genitalia, an anomaly not generally associated with this disorder. The two children were both the product of first-cousin Bedouin parents from the same family. It is possible that both sets of parents were heterozygous for CCA; thus the infants may have been homozygous for CCA, which is usually an autosomal dominant condition. No instance of homozygous CCA has previously been reported. This family suggests genetic heterogeneity in CCA and that, in some rare families, the mode of inheritance may be autosomal recessive.