Clefting, amniotic bands, and polydactyly: a distinct phenotype that supports an intrinsic mechanism for amniotic band sequence.

Amniotic band sequence (ABS) is a well-described condition involving a variety of congenital anomalies in association with fibrous bands. However, many cases are associated with birth defects that are not readily explained by the mechanism of fibrous strings entangling body parts and causing disruption of the fetal structures. The most common of these is typical cleft lip and palate (CLP). Here we describe such a case, with typical ABS limb defects and constriction bands, along with CLP, supernumerary left nipple, polydactyly, and a skin papilla. This case is nearly identical to a child previously described by Guion-Almieda and Richieri-Costa [2000] and may, therefore, represent a previously unrecognized syndrome that overlaps with ABS. Furthermore it may be that cases with ABS-like anomalies associated with CLP represent a different condition, possibly caused by mutations in the genes Disorganization, p63, or IRF6.