BLOC1S3 gene

Overview

Gene (OMIM No.)	BLOC1S3 (#609762)
Function of gene/protein	Protein: Subunit 3 of Biogenesis of lysosomal organelles complex 1 (BLOC-1) Involved in the normal biogenesis of lysosome-related organelles such as melanosomes and platelet dense granules Also proposed to play a role in neurite extension (from UniProt)
Clinical phenotype (OMIM phenotype no.)	Hermansky-Pudlak syndrome 8 (#614077)
Inheritance	Autosomal recessive
Ocular features	Albinism
Systemic features	Skin and hair depigmentation Bleeding diathesis (easy/prolonged bleeding, easy bruising, prolonged/heavy menorrhagia, epistaxis)
Key investigations	Orthoptic assessment and refraction OCT to detect foveal hypoplasia Visual evoked potentials to detect evidence of chiasmal misrouting Eye movement recordings Systemic assessment with a pediatrician, haematologists and other relevant specialists
Molecular diagnosis	Next generation sequencing Targeted gene panels (albinism) Whole exome sequencing Whole genome sequencing
Management	Ocular Management of albinism Systemic Multidisciplinary approach
Therapies under research	None in clinical trials at present
Further information	Medline Plus

Starcevic M, Dell’Angelica EC. Identification of snapin and three novel proteins (BLOS1, BLOS2, and BLOS3/reduced pigmentation) as subunits of biogenesis of lysosome-related organelles complex-1 (BLOC-1). J Biol Chem. 2004;279(27):28393-28401
Morgan NV, Pasha S, Johnson CA, et al. A germline mutation in BLOC1S3/reduced pigmentation causes a novel variant of Hermansky-Pudlak syndrome (HPS8). Am J Hum Genet. 2006;78(1):160-166
Cullinane AR, Curry JA, Golas G, et al. A BLOC-1 mutation screen reveals a novel BLOC1S3 mutation in Hermansky-Pudlak Syndrome type 8. Pigment Cell Melanoma Res. 2012;25(5):584-591

Updated on November 30, 2020