ASAH1 and asthma: Similar to ASAH1, ACER3 is one of three alkaline ceramidases (ACERs) that catalyze the conversion of ceramide to sphingosine. Furthermore, sphingolipids, as bioactive molecules, are consistently implicated in lung inflammation and airway hyperreactivity, and genetically altered sphingolipid metabolism could affect airway resistance and may predispose patients to the development of asthma [49].