The notable findings in PD datasets are briefly presented as follows: (a) increased expression levels in PD SN (Fig. 2a, within GSE26927: ATP1A1 and PLCG1; but also note decreased expression of PLCG1 within the dataset GSE7621), (b) decreased expression levels in PD SN (Fig. 2a, within GSE26927: ATP2A2; RYR1, VDAC1, GRM5) and (c) increased expression levels in PD DMX (Fig. 2a, in GSE43490: ATP2A2 and PLCG1). This evidence concerns the gene GRM5 and Parkinson disease.