Training & Education - Epidemiology Summary
- Reported U.S. population prevalence estimates of iron overloading (based on random non-fasting elevated transferrin saturation, TS values) range from 1% to 6%.
- A lower percentage of people who initially have a random elevated TS also have persistently elevated TS: estimates range from 35% to 50%.
- An even lower percentage of people with persistently elevated TS measures also have elevated serum ferritin values.
- Thus, the proportion of people who will develop clinical signs and symptoms of hemochromatosis is even lower than the proportion of people with elevated serum ferritin, SF values.
HFE gene mutations
- Two HFE gene mutations, C282Y and H63D, account for the majority of hereditary hemochromatosis cases; C282Y is most common.
- Hereditary hemochromatosis is inherited in an autosomal recessive pattern.
HFE genotype frequencies
- The population prevalence of HFE mutations depends on race and ethnicity but is most prevalent among persons of European origin and descent.
- Of people with HFE gene mutations, only a subset will develop an elevated TS. Of those with an elevated TS, only a subset will develop an elevated SF. Of those with an elevated SF, only a subset will develop hemochromatosis symptoms. Of those with symptoms, only a subset will develop clinical signs consistent with hemochromatosis.
- Most clinicians reserve the hemochromatosis diagnosis for patients whose signs and symptoms are clearly referable to documented iron overload as reflected by serum iron testing measurements.
- Iron status testing is more clinically relevant than genetic testing for identifying those who have hemochromatosis.
- At this time, CDC does not recommend population screening for HFE gene mutations because of the uncertainty about what proportion of people with HFE gene mutations will develop hemochromatosis.
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- Centers for Disease Control and Prevention
National Center on Birth Defects and Developmental Disabilities
Division of Blood Disorders
1600 Clifton Road
Atlanta, GA 30333
TTY: (888) 232-6348
- Contact CDC-INFO