We detected four potential SNP-outliers in the association between MPB and KC phenotypes (rs2669871 [near KRT75], rs3847069 [near CUX1], rs1805007 [non-synonymous functional SNP in MC1R], rs12203592 [functional SNP in an enhancer for IRF429]); outliers were also confirmed via manual inspection of MR scatter plots (Fig. 3) and funnel plots (Supplementary Figs. 6–9). The gene discussed is CUX1; the disease is keratoconus.