DNAJB1 and Parkinson disease: Furthermore, recent genetic and biological studies suggest that Hsp40/DnaJ family genes/proteins directly or cooperatively influence on the initiation of familial Parkinson's disease (PD) and other inherited forms of parkinsonism (Figure 2 and Table 1; Gorenberg and Chandra, 2017; Hasegawa et al., 2017; Puschmann, 2017).