hair disease hypotrichosis OMIM:PS605389 MESH:D007039 DOID:4535 UMLS_CUI:C0020678 A hair disease that is characterized by sparse hair on the scalp resulting from abnormal hair follicle development and has_material_basis in mutations in proteins involved in hair growth, division or proliferation of cells within hair follicles. disease_ontology SNOMEDCT_US_2020_03_01:53602002 Xref MGI. ORDO:55654