TF and Tangier disease: Serum ferritin concentrations are reportedly increased in 80% of men (>300 μg/L) and 50% of women (>200 μg/L) with p.C282Y homozygosity.32 In an Australian population cohort of median age 65 years, serological evidence of iron overload (serum ferritin ≥1000 μg/L, considered serious by the original authors) was found in 35% of male and 6% of female p.C282Y homozygotes.23 In a study of genotyped patients in eMERGE clinical biobanks across seven US health systems,31 100% of the male and 50% of the female p.C282Y homozygotes had transferrin saturations above 50%.