C/CTwo copies of the H63D variant. Published research associates this genotype with mildly elevated iron-overload risk on its own — substantially less than two copies of C282Y (rs1800562), but still worth knowing, especially alongside that result.
G/COne copy of the H63D variant. On its own, published research associates this genotype with minimal added iron-overload risk — but combined with a C282Y variant (see rs1800562) on the other gene copy, risk is meaningfully elevated.
G/GNo copies of the H63D variant. Published research does not associate this genotype with elevated hereditary hemochromatosis risk from this variant.
This variant is usually interpreted together with C282Y (rs1800562) — check that result too. If you carry either variant, a ferritin/iron panel blood test is a reasonable conversation to have with a doctor.
Source: Feder et al. 1996, Nature Genetics — a novel MHC class I-like gene (HFE) mutated in patients with hereditary haemochromatosis.