Lateral deviation of the great toe (i.e., in the direction of the little toe).

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 CIBAR1 gene (617273) on chromosome 8q22; and PAPA10 (618498), caused by mutation in the KIAA0825 gene (617266) on chromosome 5q15.

Hypoplastic/small middle phalanx of the fifth finger.

Syndactyly with fusion of toes four and five.

Presence of only one (instead of two, as normal) interphalangeal crease of the fifth finger.

Absence of the distal interphalangeal flexion creases of the fourth finger.

Behavior or an act aimed at harming a person, animal, or physical property (e.g., acts of physical violence; shouting, swearing, and using harsh language; slashing someone's tires).

A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age.

Intellectual disability, previously referred to as mental retardation, is characterized by subnormal intellectual functioning that occurs during the developmental period. It is defined by an IQ score below 70.

An abnormality in which the mandible is mislocalised posteriorly.

Head circumference below 2 standard deviations below the mean for age and gender at birth.

Distance between subnasale and pronasale more than two standard deviations above the mean, or alternatively, an apparently increased anterior protrusion of the nasal tip.

Inclination of the anterior surface of the forehead from the vertical more than two standard deviations above the mean (objective); or apparently excessive posterior sloping of the forehead in a lateral view.

Congenital anonychia is defined as the absence of fingernails and toenails. Anonychia and its milder phenotypic variant, hyponychia, usually occur as a feature of genetic syndromes, in association with significant skeletal and limb anomalies. Isolated nonsyndromic congenital anonychia/hyponychia is a rare entity that usually follows autosomal recessive inheritance with variable expression, even within a given family. The nail phenotypes observed range from no nail field to a nail field of reduced size with an absent or rudimentary nail (summary by Bruchle et al., 2008). This form of nail disorder is referred to here as nonsyndromic congenital nail disorder-4 (NDNC4). For a list of other nonsyndromic congenital nail disorders and a discussion of genetic heterogeneity, see NDNC1 (161050).