CACNA1B and Hypertension: First, the known effect of amlodipine on hypertension was reconfirmed using our new method: significant effects on hypertension were genetically predicted by variants in the genes encoding for the α1 subunits of all three calcium channel subtypes (L-type subunit α1-C, CACNA1C; T-type subunit α1-I, CACNA1I; N-type subunit α1-B, CACNA1B) and by all amlodipine target genes combined (Fig. 4C, Supplementary Table 3).