ST6GAL2 and Parkinson disease: Proteins showing the highest negative correlation in PD patients included POMGNT1 (p = 4.6E-5 and r= −0.64), TMEM132A (p = 5.7E-5 and r = −0.63), ADAM22 (p = 8.8E-5 and r = −0.62), PAM (p = 1.9E-4 and r = −0.6), and ST6GAL2 (p = 2.7E-5 and r = −0.59; Figure 6A).