The PS-2 mutant cells resembled PS-1 mutants in regard to p38 and normal cells in regard to ERK, while Trisomy 21 cells exhibited both BK-dependent p38 activation and ERK activation that was equivalent to normal fibroblasts despite showing other avenues of signal transduction that are like presenilin AD fibroblasts [8]. Here, KNG1 is linked to Alzheimer disease.