Waardenburg syndrome type 3 is an auditory-pigmentary syndrome characterized by pigmentary abnormalities of the hair, skin, and eyes; congenital sensorineural hearing loss; presence of 'dystopia canthorum,' the lateral displacement of the ocular inner canthi; and upper limb abnormalities (reviews by Read and Newton, 1997 and Pingault et al., 2010). WS type 3 is also referred to as 'Klein-Waardenburg syndrome' (Gorlin et al., 1976). Clinical Variability of Waardenburg Syndrome Types 1-4 Waardenburg syndrome has been classified into 4 main phenotypes. Type I Waardenburg syndrome (WS1; 193500) is characterized by pigmentary abnormalities of the hair, including a white forelock and premature graying; pigmentary changes of the iris, such as heterochromia iridis and brilliant blue eyes; congenital sensorineural hearing loss; and 'dystopia canthorum.' WS type II (WS2) is distinguished from type I by the absence of dystopia canthorum. WS type III has dystopia canthorum and is distinguished by the presence of upper limb abnormalities. WS type IV (WS4; 277580), also known as Waardenburg-Shah syndrome, has the additional feature of Hirschsprung disease (reviews by Read and Newton, 1997 and Pingault et al., 2010).

PCWH syndrome is a complex neurocristopathy that includes features of 4 distinct syndromes: peripheral demyelinating neuropathy (see 118200), central dysmyelination, Waardenburg syndrome, and Hirschsprung disease (see 142623) (Inoue et al., 2004). Inoue et al. (2004) proposed the acronym PCWH for this disorder.

Familial progressive hyperpigmentation with or without hypopigmentation (FPHH) is characterized by diffuse hyperpigmentation of variable intensity sometimes associated with cafe-au-lait macules and larger hypopigmented ash-leaf macules. These features, which involve the face, neck, trunk, and limbs, are seen at birth or develop early in infancy (summary by Wang et al., 2009 and Amyere et al., 2011). Also see familial progressive hyperpigmentation (FPH1; 614233).

Waardenburg syndrome type 4 (WS4), also known as Waardenburg-Shah syndrome, is an auditory-pigmentary syndrome characterized by pigmentary abnormalities of the hair, skin, and eyes, congenital sensorineural hearing loss, and Hirschsprung disease (reviews by Read and Newton, 1997 and Pingault et al., 2010). WS type 4A is caused by mutation in the EDNRB gene (131244). Clinical Variability of Waardenburg Syndrome Types 1-4 Waardenburg syndrome has been classified into 4 main phenotypes. Type I Waardenburg syndrome (WS1; 193500) is characterized by pigmentary abnormalities of the hair, including a white forelock and premature graying; pigmentary changes of the iris, such as heterochromia iridis and brilliant blue eyes; congenital sensorineural hearing loss; and 'dystopia canthorum.' WS type II (WS2) is distinguished from type I by the absence of dystopia canthorum. WS type III (WS3; 148820) has dystopia canthorum and is distinguished by the presence of upper limb abnormalities. WS type 4 has the additional feature of Hirschsprung disease (reviews by Read and Newton, 1997 and Pingault et al., 2010). Genetic Heterogeneity of Waardenburg Syndrome Type 4 Waardenburg syndrome type 4 is genetically heterogeneous. WS4B (613265) is caused by mutation in the EDN3 gene (131242) on chromosome 20q13, and WS4C (613266) is caused by mutation in the SOX10 gene (602229) on chromosome 22q13.

Waardenburg syndrome type 2 (WS2) is an auditory-pigmentary syndrome characterized by pigmentary abnormalities of the hair, skin, and eyes; congenital sensorineural hearing loss; and the absence of 'dystopia canthorum,' the lateral displacement of the inner canthus of each eye, which is seen in some other forms of WS (review by Read and Newton, 1997). Individuals with WS type 2E (WS2E) may have neurologic abnormalities, including mental impairment, myelination defects, and ataxia. Waardenburg syndrome type 2 is genetically heterogeneous (see WS2A, 193510). For a description of other clinical variants of Waardenburg syndrome, see WS1 (193500), WS3 (148820), and WS4 (277580).

Waardenburg syndrome type 4 is an auditory-pigmentary syndrome characterized by pigmentary abnormalities of the eye, deafness, and Hirschsprung disease (review by Read and Newton, 1997). WS type 4C is caused by mutation in the SOX10 gene (602229). WS type 4 is genetically heterogeneous (see WS4A; 277580). For a description of other clinical variants of Waardenburg syndrome, see WS1 (193500), WS2 (193510), and WS3 (148820).

Waardenburg syndrome type 4 is an auditory-pigmentary syndrome characterized by pigmentary abnormalities of the eye, deafness, and Hirschsprung disease (review by Read and Newton, 1997). WS type 4B is caused by mutation in the EDN3 gene (131242). WS type 4 is genetically heterogeneous (see WS4A; 277580). For a description of other clinical variants of Waardenburg syndrome, see WS1 (193500), WS2 (193510), and WS3 (148820).