Interestingly, the Y402H CFH loss-of-function mutation linked to AMD in many human populations may produce sufficient amounts of a non-functioning CFH, and this may be pathologically equivalent to insufficient amounts of a functional CFH protein, as is observed in sporadic AD, and perhaps other inflammatory degenerative and dementing diseases including Down’s syndrome [Trisomy 21; (10, 25, 37)]. The gene discussed is CFH; the disease is Down syndrome.