Molecular analysis of patients suspected of Fragile X Syndrome.

The aim of this study was to validate the molecular genetic diagnosis of patients suspected of Fragile X Syndrome (FXS) in the Laboratory of Human Cytogenetics and Molecular Genetics (LaGene) of the Department of Health of the State of Goiás, using polymerase chain reaction (PCR). Thirty-five patients referred by public health doctors to LaGene, indicating clinical diagnosis of FXS, were selected for this study. Two PCR analyses were performed using different primers, one for screening (PCR-T) and one for the detection of the pre-mutation (PCR-P). The products of both PCRs were subjected to polyacrylamide gel electrophoresis and then coloring. The visualization of amplicons was performed with the aid of an ultraviolet transilluminator. The diagnosis was confirmed in 88% of patients with PCR-T and 100% with PCR-P. The primer used in PCR-P was found to be more sensitive and specific, allowing to identify the mutation in the samples, generating a more conclusive case for FXS, noting that the PCR-T is also required for the pre-classification of patients. Generally, the PCR technique is cheaper and easier to handle; therefore, we suggest the implementation of PCR in the genetics laboratory of the State of Goiás (LaGene) for the diagnosis of FXS.

Lack of association between IL-10 -1082G/A polymorphism and chronic periodontal disease in adults.

Because of the complex interaction between periodontal pathogens and the host defense system, periodontitis is considered an inflammatory disorder of bacterial etiology that results in periodontal tissue damage. Genetic mechanisms may interfere with the gene expression of important inflammation mediators, modulating the immunologic response of an individual. In this study, we evaluated the single nucleotide polymorphism -1082G/A in the promoter region of interleukin-10 gene and its relationship with periodontal disease in Central Brazil. We included 36 cases classified according to disease severity (mild, moderate, or severe) and 30 controls. The allelic distribution of the cases was 16 (44%) AG, followed by 13 (36%) GG and 7 (20%) with the genotype AA. In the control group, 13 (43%) presented the genotype AG, 12 (40%) GG and 5 (17%) were classified as AA. The populations examined were in Hardy-Weinberg equilibrium. Analysis of allelic and genotypic frequencies revealed no casual relationship with the presence of genotype G or A and the development of periodontal disease in adults. The single nucleotide polymorphism -1082G/A of the interleukin-10 gene was not predictive of periodontal disease.

Assessment of BCL2/J(H) translocation in healthy individuals exposed to low-level radiation of 137CsCl in Goiânia, Goiás, Brazil.

Healthy radio-exposed individuals who received low levels of Cesium-137 radiation during the accident that occurred in Goiânia in 1987, their families and controls were tested for the detection of t(14;18)-rearranged B cells in peripheral blood by using a highly sensitive, real-time quantitative PCR method. The chromosomal translocation t(14;18)(q32;q21) is characteristic of follicular lymphoma and is a frequent abnormality observed in other types of non-Hodgkin's lymphoma. This translocation leads to constitutive activation of the BCL2 oncogene by the enhancers of the immunoglobulin heavy-chain locus. In healthy individuals, the same translocation may also be found in a small fraction of peripheral blood lymphocytes, and positive cells might serve as an indicator for environmental exposure to carcinogens and possibly correlate with the cumulative risk of developing t(14;18)- positive non-Hodgkin's lymphoma. Twenty healthy radio-exposed individuals, 10 relatives and 10 non-exposed healthy individuals were tested for the detection of this translocation. Only 1 non-exposed individual was positive for the chromosomal translocation, and healthy radio-exposed individuals presented lower levels of cells bearing the BCL2/J(H) rearrangement when compared to the levels of the patients with follicular lymphoma before treatment. However, evaluation of more cells would be required to confirm the total absence of circulating cells bearing BCL2/J(H) rearrangement.