The function of Ensembl gene identifier ENSG00000135587 (SMPD2, sphingomyelin phosphodiesterase 2) is as follows. Catalyzes, at least in vitro, the hydrolysis of sphingomyelin to form ceramide and phosphocholine (PubMed:10608884). Also hydrolyzes 1-O-alkyl-2-lyso-sn-glycero-3-phosphocholine (lyso-platelet-activating factor) in vivo (PubMed:10608884). Also acts on 1-acyl-2-lyso-sn- glycero-3-phosphocholine (lyso-PC) and sphingosylphosphocholine (PubMed:10608884, PubMed:14741383). {ECO:0000269|PubMed:10608884, ECO:0000269|PubMed:14741383}.