Polydactyly refers to the occurrence of supernumerary digits and is the most frequent of congenital hand and foot deformities. Based on the location of the extra digits, polydactyly can be classified into preaxial, involving the thumb or great toe; postaxial, affecting the fifth digit; and central, involving the 3 central digits. Postaxial polydactyly (PAP) is further subclassified into 2 types: in type A, a well-formed extra digit articulates with the fifth or a sixth metacarpal, whereas in type B, a rudimentary, poorly developed extra digit is present (summary by Umm-e-Kalsoom et al., 2012). Genetic Heterogeneity of Postaxial Polydactyly Other forms of postaxial polydactyly type A include PAPA2 (602085) on chromosome 13q21; PAPA3 (607324) on chromosome 19p13; PAPA4 (608562) on chromosome 7q22; PAPA5 (263450) on chromosome 13q13; PAPA6 (615226), caused by mutation in the ZNF141 gene (194648) on chromosome 4p16; PAPA7 (617642), caused by mutation in the IQCE gene (617631) on chromosome 7p22; PAPA8 (618123), caused by mutation in the GLI1 gene (165220) on chromosome 12q13; PAPA9 (618219), caused by mutation in the FAM98A gene (617273) on chromosome 8q22; and PAPA10 (618498), caused by mutation in the KIAA0825 gene (617266) on chromosome 5q15.

Limb shortening because of underdevelopment of one or more bones of the extremities.

The legs angle inward, such that the knees are close together and the ankles far apart.

A congenital heart defect characterized by a specific combination of heart defects with a common atrioventricular valve, primum atrial septal defect and inlet ventricular septal defect.

A defect of the atrioventricular septum of the heart.

Abnormally small dimension of the Maxilla. Usually creating a malocclusion or malalignment between the upper and lower teeth or resulting in a deficient amount of projection of the base of the nose and lower midface region.

Increased inferior to superior extent of the thorax.

Increased space between two adjacent teeth in the same dental arch.

An abnormal conical form of the teeth, that is, a tooth whose sides converge or taper together incisally.

Positioning of the nasal tip inferior to the nasal base.

Facial height (length) is more than 2 standard deviations above the mean (objective); or, an apparent increase in the height (length) of the face (subjective).

Posterior positions and/or vertical shortening of the infraorbital and perialar regions, or increased concavity of the face and/or reduced nasolabial angle.

Distance between nasal base and midline upper lip vermilion border more than 2 SD below the mean. Alternatively, an apparently decreased distance between nasal base and midline upper lip vermilion border.

Extra fold of tissue extending from the alveolar ridge to the inner surface of the upper or lower lip.

The presence of developmental dysplasia of the nail.