Recent work reports evidence that CFTR is a causal T1D gene (Chiou et al. 2021), even though the GWAS signal proximal to this gene, at 7q31.2, has a relatively small effect, with priorityFDR = 8.88 × 10−3 and OR = 1.08 (1.05–1.11), and was not included in either red or blue prioritisation groups. Here, CFTR is linked to type 1 diabetes mellitus.