Medium-sized components of the human disease map. The figure shows three medium-sized components of the disease map with some disease names highlighted. One group (A) comprises variants of congenital mental retardation, eye abnormalities, tooth abnormalities as well as glaucoma, cataract and renal tubular acidosis. Retinal diseases, blindness as well as hearing loss and deafness are joined in another group (B). The third disease group (C) contains Parkinsonian disorders, Alzheimer disease, dementia, as well as bipolar disorder and alcoholism.