Brazi. Rev. Bras. Hematol. Hemoter. 2008;30(5):379-383.

ABSTRACT. Development of hereditary hemochromatosis is associated with the C282Y, H63D or S65C mutations in the hemochromatosis gene. Though there is extensive knowledge about the former two, there is little information on the mechanism of action and the allelic frequency of the S65C mutation. We examined the prevalence of the S65C mutation of the hemochromatosis gene in Brazilians with clinical suspicion of hereditary hemochromatosis. Genotyping for this mutation was carried out in 633 individuals with clinical suspicion of hereditary hemochromatosis, using the polymerase chain reaction, followed by enzymatic digestion. The sample comprised 77.1% men and 22.9% women, giving a ratio of approximately 3:1; the mean age was 48.8 + 13.8 years. More than half (57.3%) of the individuals in the sample were 41 to 60 years old. The frequency of heterozygotes for this mutation was 0.016; no homozygous mutant patients were found. S65C mutation in BrazilThis is the first analysis of the S65C mutation in individuals suspected of having hereditary hemochromatosis in Brazil.

ABSTRACT. In view of the serious consequences of mediumchain acyl-CoA dehydrogenase (MCAD) deficiency and the absence of information about its incidence in the Brazilian population, we examined the frequency of the A985G mutation in the MCAD gene. A retrospective analysis was made of data on 1722 individuals (844 females) genotyped for the A985G mutation in the MCAD gene, using genomic DNA extracted from peripheral blood leukocytes and genotyping with PCR-RFLP; 0.41% of these individuals were heterozygous for the A985G mutation. The mutant homozygous genotype was not found. The 985G mu- tant and 985A normal alleles had allelic frequencies of 0.0020 and 0.9980, respectively. Given the A985G allele frequency, genotyping would be recommended in cases of family history of MCAD deficiency and sudden infant death syndrome, and when there is suspicion of medium-chain fatty acid metabolic alterations; genetic counseling should be offered in cases involving 985GG and A985G individuals and consanguineous marriages.