Previous studies proved that cis-acting elements were responsible for AS of many genes (Black, 2003; Higashide et al., 2004; Stamm et al., 2005), e.g., presenilin 2 (PS2) gene, which was abnormally alternatively spliced in a sample related to Alzheimer's disease (Higashide et al., 2004). The gene discussed is PSEN2; the disease is early-onset autosomal dominant Alzheimer disease.