All CD assumptions come from the alteration of SFRP-1, as elevated levels of this protein have been found to be directly associated with Alzheimer’s disease and other CD.37 The bU[−] phenotype displayed elevated SFRP-1,37-39 suggesting that this phenotype has more risk of CD than the bU[+]. Here, SFRP1 is linked to early-onset autosomal dominant Alzheimer disease.