Abnormally small penis. At birth, the normal penis is about 3 cm (stretched length from pubic tubercle to tip of penis) with micropenis less than 2.0-2.5 cm.

Webbing or fusion of the fingers or toes, involving soft parts only or including bone structure. Bony fusions are referred to as "bony" syndactyly if the fusion occurs in a radio-ulnar axis. Fusions of bones of the fingers or toes in a proximo-distal axis are referred to as "symphalangism".

Increased thumb width without increased dorso-ventral dimension.

Type B1 brachydactyly (BDB1) is the most severe type of human brachydactyly, and shows high penetrance and variable expressivity. Hypoplastic or absent distal phalanges and nails of digits 2 through 5 in the hands and feet are cardinal phenotypic features of BDB1. The middle phalanges of digits 2 through 5 are usually short and may form a bony fusion with the corresponding hypoplastic distal phalanges. The deformed thumbs are often flat, broad, or bifid. A rarer feature of BDB1 is cutaneous syndactyly affecting both fingers and toes (summary by Lv et al., 2009).

Short (hypoplastic) middle phalanx of finger, affecting one or more fingers.

Absence or underdevelopment of the distal phalanges.

A soft tissue continuity in the A/P axis between two fingers that extends distally to at least the level of the proximal interphalangeal joints, or a soft tissue continuity in the A/P axis between two fingers that lies significantly distal to the flexion crease that overlies the metacarpophalangeal joint of the adjacent fingers.

Absence or underdevelopment of the distal phalanges of the toes.

A hole between the two bottom chambers (ventricles) of the heart. The defect is centered around the most superior aspect of the ventricular septum.

Contractures of one ore more joints of the hands meaning chronic loss of joint motion due to structural changes in non-bony tissue.

Absence of one half of the vertebral body.

Infants normally have two fontanels at birth, the diamond-shaped anterior fontanelle at the junction of the coronal and sagittal sutures, and the posterior fontanelle at the intersection of the occipital and parietal bones. The posterior fontanelle usually closes by the 8th week of life, and the anterior fontanel closes by the 18th month of life on average. This term applies if there is delay of closure of the fontanelles beyond the normal age.

The distal interphalangeal joint and/or the proximal interphalangeal joint of the fingers or toes cannot be extended to 180 degrees by either active or passive extension.

One or more abnormally short long bone.

Enlargement of the anterior fontanelle with respect to age-dependent norms.

A developmental defect leading to the union of two adjacent vertebrae.

Delayed tooth eruption affecting the secondary dentition.

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).

Underdevelopment of a fingernail.