Using the multivariate forward likelihood method with adjustments for age, sex, splenectomy, and iron chelating drug use, we found that only the LF/HF (odds ratio 8.710, 95% CI 2.324–32.649, P = 0.001), but not the mean Hb in the last 12 months significantly correlated with CMR T2*. This evidence concerns the gene GSTM1 and hydrops fetalis.