Zlotogora and Nubani described a family is in which four subjects in two sibships had typical SHFM This also suggests an autosomal recessive form of the disorder.
Klein also reported ectrodactyly in two siblings born out of mating between a man and the daughter of his half-brother. Ray and Freire-Maia also reported autosomal recessive ectrodactyly.
described split-hand and split-foot in two sibships born out of consanguineous marriage and indicated that split-hand and -foot deformity can be inherited as an autosomal recessive trait. There have been isolated case reports in the literature of the autosomal recessive inheritance pattern of SHFMs of the non-syndromal type. However, in our case, the probable inheritance pattern is autosomal reccesive as only siblings and no other family member are affected. The non-syndromal SHFM limited to the hands and feet usually follows the pattern of inheritance of a regular autosomal dominant gene with a high penetrance. The syndromic form has a variable degree of expression. Type I, the most frequent variety, is due to a mutation on chromosome 7 in a region that contains two homeobox genes, DLX5 and DLX6. Our case belongs to the non-syndromic type of SHFM as there is no associated anomaly.įive different genetic mutations are known to be associated with SHFM. Two expressions of SHFM occur, one with isolated involvement of the limbs, known as the non-syndromic form, and the second, the syndromic form, with associated anamolies such as tibial aplasia, mental retardation, ectodermal and craniofacial findings, orofacial clefting and deafness. Its incidence has been reported to be about 1 in 90,000 babies with no sex predeliction. SHFM involves median clefts of the hands and feet with associated syndactyly, aplasia and/or hypoplasia of the phalanges, metacarpals and metatarsals.