Griscelli Syndrome, Type 3

A number sign (#) is used with this entry because Griscelli syndrome type 3 (GS3), which is characterized by hypomelanosis with no immunologic or neurologic manifestations, can be caused by mutation in the melanophilin (MLPH; 606526) or MYO5A (160777) genes.

For a discussion of phenotypic and genetic heterogeneity in Griscelli syndrome, see the entry for GS1 (214450).

Clinical Features

Sanal et al. (2002) reported 2 patients with silver-gray hair, eyebrows, and eyelashes who had large clumps of pigment, typical of Griscelli syndrome, on microscopic analysis of their hair shafts. The patients developed no other manifestations over 6 and 8 years of follow-up, respectively.

Molecular Genetics

In the 2 patients reported by Sanal et al. (2002) with hypopigmentation without any immunologic or neurologic manifestations, Menasche et al. (2003) identified a homozygous mutation in the MLPH gene (606526.0001) in 1 patient and homozygous deletion of the F-exon of the MYO5A gene (160777.0004) in the other.