Importance of 5569G/A polymorphism in intron 4 of HFE gene in the diagnosis of hereditary hemochromatosis

BACKGROUND: The presence of the 5569A polymorphism may lead to misdiagnosis of patients susceptible of hereditary hemochromatosis (HH). For that reaso n, samples containing the Cys282Tyr mutation were revised and the frequency of this polymorphism in our environment was assessed. PATIENTS AND METHOD: Twenty samples were retested and 56 controls were incl uded. The study was performed by PCR-RFLP. RESULTS: The diagnosis was confirmed in 8 cases susceptible of error. Howev er, an amplification deficiency of normal alleles was detected in 2 heteroz ygous (17%). The allelic frequency of the 5569A polymorphism in the control population was 14.3%. CONCLUSIONS: Although misdiagnosis was not committed, we recommend changing to any primer that does not include the 5569G/A polymorphism in the study of HH.