Required for osteoclast and melanocyte maturation and function.
Involvement in disease
Defects in OSTM1 are the cause of osteopetrosis autosomal recessive type 5 (OPTB5) [MIM:259720]; also called infantile malignant osteopetrosis 3. Osteopetrosis is a rare genetic disease characterized by abnormally dense bone, due to defective resorption of immature bone. The disorder occurs in two forms: a severe autosomal recessive form occurring in utero, infancy, or childhood, and a benign autosomal dominant form occurring in adolescence or adulthood. OPTB5 patients manifest primary central nervous system involvement in addition to the classical stigmata of severe bone sclerosis, growth failure, anemia, thrombocytopenia and visual impairment with optic atrophy.