SLC9A6 and lysosomal storage disease: In the null mouse model, both mutant male (Nhe6-/Y) and homozygous female (Nhe6−/−) knockout mice exhibit impaired endo-lysosomal function (i.e., aberrant accumulation of GM2 ganglioside and cholesterol) in subpopulations of neurons within the amygdala, hippocampus, hypothalamus and cerebral cortex as well as pronounced formation of axonal spheroids and degeneration of cerebellar Purkinje cells, features typical of many lysosomal storage diseases [26, 100].