Firth logistic regression identified two genes with a significantly different enrichment of nonsynonymous rare variants in one cohort when compared to another (Table 4), including an enrichment of variants in NOTCH3 in the PD cohort compared to the combined AD and MCI cohort (OR = 2.986, p = 0.009), and an enrichment of variants in NEFH in the combined AD and MCI cohort compared to the CVD cohort (OR = 0.272, p = 0.011). Here, NEFH is linked to Alzheimer disease.