Hereditary
Hemochromatosis (HH) is the most common genetic disorder known, with a
prevalence of 1/200 and a carrier frequency of 1/8 in Caucasians. This
disorder involves excess iron absorption and storage in organs and
leads to high morbidity and mortality if untreated. Historically, most
cases have remained undiagnosed until late in the course of the disease
when irreversible damage has already occurred. Early diagnosis allows
for prevention of symptoms through treatment by phlebotomy.
Two
mutations associated with hemochromatosis have been discovered in the
HFE gene. The major mutation, Cys282Tyr (also known as 845A) is present
in the homozygous state in 85% of Caucasians with clinically diagnosed
hemochromatosis. Most homozygotes (with two copies of the mutation) and
some heterozygotes (with one copy of the mutation) develop iron
overload and hemochromatosis. A second mutation, His63Asp (also known
as 187G), appears to somewhat increase risk of iron overload. Although
only a small percent of individuals (up to 6%) with this mutation
develop hemochromatosis, DNA testing for hemochromatosis provides for
effective early diagnosis and prevention.
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- Indications for Hemochromatosis
DNA Testing:
 | Elevated transferrin saturation (>50%) or serum ferritin concentration (>400 ng/ml in men and >200 ng/ml in women) | | Clinical diagnosis of hemochromatosis | | Unexplained elevated serum concentrations of liver enzymes | | Cirrhosis, liver failure, or hepatocellular carcinoma | | Chronic unexplained fatigue, abdominal pain, or joint pain | | Hepatosplenomegaly,
cardiac arrhythmia, congestive heart failure, hyperpigmentation,
hypothyroidism, impotence, hypogonadism, diabetes mellitus | | Relative or spouse with hemochromatosis | | Relative or spouse known to be homozygous or heterozygous for the Cys282Tyr mutation |
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| Our Hemochromatosis DNA Test Service Provides:
| PCR analysis for both the Cys282Tyr and the His63Asp mutations | | Rapid (1 day) turnaround time | | Detailed reports with genetic interpretation, recommendations and education | | Genetic consultation by board-certified genetic counselors and geneticists |
Specimen Requirements:
| • | Cheek cell sample OR 5 ml blood in an EDTA (lavender top) tube
| | • | Send at room temperature; samples are stable for several days |
Turnaround Time:
Please call Kimball Genetics for more information.
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