For example, TGase2 may contribute to the formation of crystallin polymers in age-related cataracts (6), the aggregation of huntingtin protein with an expanded polyglutamine domain as occurs in Huntington’s disease (7), and the accumulation of insoluble neurofibrillary tangles and β-amyloid plaques in Alzheimer’s disease (8,9). The gene discussed is TGM2; the disease is Huntington disease.