Since polymorphisms in the ABCA5 gene appear protective against PD15 and the fact that ABCA5 is a lysosomal transporter that mediates the removal of excess sphingomyelin from lysosomes, we were interested in understanding if ABCA5 was changed in PD and measured the expression of ABCA5 in the same tissue samples as the lipid analysis. Here, ABCA5 is linked to Parkinson disease.