Focal dermal hypoplasia is a multisystem disorder characterized primarily by involvement of the skin, skeletal system, eyes, and face. Skin manifestations present at birth include atrophic and hypoplastic areas of skin; cutis aplasia; fat nodules in the dermis manifesting as soft, yellow-pink cutaneous nodules; and pigmentary changes. Verrucoid papillomas of the skin and mucous membranes may appear later. The nails can be ridged, dysplastic, or hypoplastic; hair can be sparse or absent. Limb malformations include oligo-/syndactyly and split hand/foot. Developmental abnormalities of the eye can include anophthalmia/microphthalmia, iris and chorioretinal coloboma, and lacrimal duct abnormalities. Craniofacial findings can include facial asymmetry, notched alae nasi, cleft lip and palate, and pointed chin. Occasional findings include dental anomalies, abdominal wall defects, diaphragmatic hernia, and renal anomalies. Psychomotor development is usually normal; some individuals have cognitive impairment.

Freeman-Sheldon syndrome (FSS), or DA2A, is phenotypically similar to DA1. In addition to contractures of the hands and feet, FSS is characterized by oropharyngeal abnormalities, scoliosis, and a distinctive face that includes a very small oral orifice (often only a few millimeters in diameter at birth), puckered lips, and an H-shaped dimple of the chin; hence, FSS has been called 'whistling face syndrome.' The limb phenotypes of DA1 and FSS may be so similar that they can only be distinguished by the differences in facial morphology (summary by Bamshad et al., 2009). For a general phenotypic description and a discussion of genetic heterogeneity of distal arthrogryposis, see DA1 (108120).

A rare neurologic disease typically characterized by the triad of eye, central nervous system and skin malformations, and often associated with an intellectual disability.

A very rare dysmorphic disorder characterized by hypoplasia and coloboma of the alar cartilages and telecanthus described in 2 sisters. No new cases with similar features have been reported since 1976.

Frontonasal dysplasia-2 (FND2) is an autosomal recessive disorder characterized by variable degrees of alopecia, skull defects, hypertelorism, depressed nasal bridge and ridge with notched alae nasi, and abnormal central nervous system findings (summary by Kariminejad et al., 2014).

Alar clefts most commonly occur in association with cleft lip and/or other craniofacial anomalies. The basic embryonic mechanism in alar clefts involves failure of fusion between the medial and the lateral nasal processes during the sixth to tenth weeks. The medial process gives rise to one-half of the nasal septum and the medial crus of the lower lateral alar cartilage, and the lateral process gives rise to the external wall of the nose, nasal bones, upper lateral cartilage, alae, and lateral crus of the lower lateral cartilage. The dorsum and apex of the nose, which are derived from the frontonasal process, are usually well preserved in patients with isolated alar cleft (summary by Richieri-Costa and Guion-Almeida, 2009).

Fraser syndrome is an autosomal recessive malformation disorder characterized by cryptophthalmos, syndactyly, and abnormalities of the respiratory and urogenital tract (summary by van Haelst et al., 2008). Genetic Heterogeneity of Fraser Syndrome Fraser syndrome-2 (FRASRS2) is caused by mutation in the FREM2 gene (608945) on chromosome 13q13, and Fraser syndrome-3 (FRASRS3; 617667) is caused by mutation in the GRIP1 gene (604597) on chromosome 12q14. See Bowen syndrome (211200) for a comparable but probably distinct syndrome of multiple congenital malformations.