In multiple linear regression after adjustment for confounding factor (hemochromatosis type) the associations were still significant between R2* ROI and VSF (β = − 0.39, 95% CI − 0.21 to − 0.04, p = 0.005) and IMF (β = 0.32, 95% CI 0.05 to 0.69, p = 0.024), whereas the association to SCF was without statistical significance (β = 0.27, 95% CI − 0.01 to 0.25, p = 0.052). This evidence concerns the gene KITLG and hemochromatosis type 1.