The top five SNPs for the age at the first cigarette are listed in Table 3. In the time‐to‐event analysis rs73050610 on 19q13.33 was highlighted (P = 1.12e‐07) (Fig. S1, Table 3). In a follow‐up analysis additionally adjusted for first time sensations rs73050610 achieved genome‐wide significance (P = 3.37e‐08) (Fig. S2, Table 3). The LD block in which all top five SNPs are located is flanked by genes TRPM4 (1 kb apart) and SLC6A16 (60 kb apart). A regional plot of the 19q13.33 locus is shown in Figure S3. In an analysis conditioned on rs73050610, no residual genome‐wide significant signal remained, suggesting that there is only one independent signal in this locus. The hazard ratio (HR) of rs73050610 is 0.80, suggesting that carriers of the minor allele have a 20% lower hazard per allele of smoking the first whole cigarette.
