Mutation in saposin D domain of sphingolipid activator protein gene causes urinary system defects and cerebellar Purkinje cell degeneration with accumulation of hydroxy fatty acid-containing ceramide in the mouse. - Matsuda,J.; Kido,M.; Tadano-Aritomi,K.; Ishizuka,I.; Tominaga,K.; Toida,K.; Takeda,E.; Suzuki,K.; Kuroda,Y. (Hum Mol Genet, 2004)