ASAH1 and Farber lipogranulomatosis: Subsequently, the N‐acyl group in ceramide is removed by one of five different ceramidases which include the acid ceramidase ASAH1/AC, the neutral ceramidase ASAH2/NC, and the alkaline ceramidases 1–3 (ACER1, ACER2, ACER3) of which the lysosomal ceramidase ASAH1 is probably the most important as exemplified by the clinical consequences of ASAH1 deficiency (Farber disease).