Genes upregulated in AD included ceramide synthases CERS1 (also termed LASS1, mammalian homolog of yeast longevity-assurance gene 1) and CERS2 (LASS2), S1P lyase (SGPL1), or serine palmitoyltransferase (SPTLC2), while the acid ceramidase (ASAH1) and ceramide kinase (CERK) were reduced [12]. Here, CERS1 is linked to Alzheimer disease.