Abstract Congenital heart defects are the most common birth defects and the leading cause of mortality in the first year of life. It is well known that the 22q11 deletion syndrome (22q11DS) is the most common microdeletion syndrome in humans and that congenial heart diseases (CHDs) are one of the most common phenotypic manifestations. However, it should be noted that the 22q11 deletion was also found in a significant number of patients with isolated CHD. The 22q11DS phenotype may include cardiovascular anomalies, palatal abnormalities, nasal voice, immune deficiency, endocrine dysfunctions, a varying degree of cognitive deficits and intellectual disabilities, velopharyngeal insufficiency, and characteristic craniofacial dysmorphism. This condition affects about 1 in 4,000 live births, making 22q11DS the most common microdeletion syndrome in humans. Here we describe the cases of three children who were referred to the clinical hospital center with the diagnosis of CHD, but with no direct signs of 22q11DS. Investigation of familial data led us to suspect that the mothers could be carriers of 22q11DS. The multiplex ligation-dependent probe amplification (MLPA) testing confirmed that the patients and mothers exhibited 3 Mb 22q11 deletions, which justified the clinical signs in the mothers and the CHD in children. In the presence of a few characteristics that are common of a spectrum of some known syndromes, a familial examination can provide clues to a definitive diagnosis, as well as to the prevention of diseases and genetic counseling of these patients.

OBJETIVO: Este trabalho objetivou avaliar a qualidade do DNA obtido de saliva humana armazenada e sua aplicabilidade da identificação de pessoas. METODOLOGIA: Analisaram-se amostras salivares de n=20 sujeitos da pesquisa, coletadas nas formas de saliva in natura e de swab bucal, sendo armazenadas a 20ºC. Após 7 dias, o DNA foi extraído das 40 amostras de saliva e submetido à PCR e à eletroforese. Após 180 dias repetiu-se a técnica nas 20 amostras de swab. RESULTADOS: Os resultados da primeira etapa indicaram que o DNA foi extraído com sucesso em 97,5% das reações, e, analisando-se separadamente, em 95% de saliva in natura e em 100% da saliva do swab, não havendo diferenças estatisticamente significantes entre as duas formas de saliva. Na segunda fase, o resultado foi positivo para as 20 amostras analisadas (100%). Posteriormente, para analisar a qualidade do DNA obtido da saliva humana, o gene SIX3-2 foi testado nas 20 amostras de swab bucal e foi feita a digestão do produto da PCR com a enzima de restrição MbO1 para avaliar polimorfismo do gene ADRA-2 obtendo-se resultados positivos para a maioria das amostras. CONCLUSÃO: Concluiu-se que a quantidade e a qualidade do DNA advindo de saliva e as técnicas empregadas estão adequadas à análise forense do DNA.

PURPOSE: This study evaluated the quality of DNA obtained from stored human saliva and its applicability to human identification. METHODS: The saliva samples of 20 subjects, collected in the form of saliva in natura and from mouth swabs and stored at -20ºC, were analyzed. After 7 days, the DNA was extracted from the 40 saliva samples and subjected to PCR and electrophoresis. After 180 days, the technique was repeated with the 20 swab samples. RESULTS: The first-stage results indicated that DNA was successfully extracted in 97.5% of reactions, 95% of saliva in natura and 100% of swab saliva samples, with no statistically significant difference between the forms of saliva. In the second phase, the result was positive for all 20 analyzed samples (100%). Subsequently, in order to analyze the quality of the DNA obtained from human saliva, the SIX3-2 gene was tested on the 20 mouth swab samples, and the PCR products were digested using the MbO1 restriction enzyme to evaluate polymorphisms in the ADRA-2 gene, with positive results for most samples. CONCLUSION: It was concluded that the quantity and quality of DNA from saliva and the techniques employed are adequate for forensic analysis of DNA.