Genetic variation in CR1 has been associated with a variety of diseases, such as Alzheimer’s disease [3, 8, 9, 12, 27, 34, 36, 41, 72], Malaria [4, 37, 71, 83], and Systemic Lupus Erythematous [5, 13, 29, 35, 37, 48, 52, 53, 60, 65, 75, 78, 82]; however, in many cases the precise genetic variations have not been identified. Here, CR1 is linked to early-onset autosomal dominant Alzheimer disease.