7 genes (9%) were found to have a known role in apoptosis regulation, which therefore serve as positive controls: Among them is the Mitochondrial carrier homolog 1 (Mtch1), also known as PSAP, a transporter in mitochondria that interacts with and could mediate apoptosis by presenilin-1 in Alzheimer's disease [18]. Here, PSEN1 is linked to Alzheimer disease.