A Novel Homozygous RAB27A Mutation is Associated with Griscelli Syndrom Type II and Less Severe Presentations

Griscelli syndrome type II is a primary immunodeficiency disorder caused by a RAB27A gene mutation. It is inherited in an autosomal recessive manner and is characterized by oculocutaneous hypopigmentation and various cellular immune system deficiencies. Herein, we report a 5-year-old girl with silvery-gray hair, eyebrows, and eyelashes who was referred to our primary immune deficiency clinic because of recurrent oral thrush. Further investigations were performed to uncover the probable underlying genetic disorder. Whole-exome sequencing revealed a novel mutation in the RAB27A gene (c.137T>G) and confirmed the diagnosis of Griscelli syndrome type 2 Due to the poor prognosis nature of this disorder and also its need for differential diagnosis with some other conditions with hypopigmentation, prompt diagnosis, genetic analysis, and proper treatment are necessary for avoiding serious complications.