Etiological investigation of deafness in neonates screened in a universal newborn hearing screening program

Purpose to describe the results of etiology of deaf in neonates screened in a universal newborn hearing screening program. Methods a descriptive, cross-sectional and prospective study. The study included all newborns diagnosed with hearing loss identified in a universal newborn hearing screening program from August 2003 to December 2006. The etiology of deaf was determined after detailed anamnesis performed by the otorhinolaryngologist; survey of serological tests for toxoplasmosis, rubella, cytomegalovirus, herpes, syphilis and HIV; tomography of the temporal bone and genetic tests. Results 17 neonates were diagnosed with hearing loss in the period studied. 64.7% of cases presented as probable causes prenatal etiology, 29.4% perinatal causes and one child (5.9%) had unknown etiology. Of prenatal causes, 36.4% had confirmed genetic origin and 36.4% presumed etiology of heredity. We confirmed the presence of congenital infections in 18.2% of cases and one child (9%) had craniofacial anomalies as a possible etiology. The degree of hearing loss more frequently observed in the subjects studied was the profound (47.1%). Conclusion the increased occurrence of etiologies in this study was of prenatal origin, followed by perinatal origin.Objetivo descrever os resultados da investigação etiológica da deficiência auditiva realizada em neonatos rastreados em um programa de triagem auditiva neonatal universal. Métodos estudo descritivo, transversal e prospectivo. Foram incluídos no estudo todos os neonatos diagnosticados com deficiência auditiva identificados em um programa de triagem auditiva neonatal universal no período de agosto de 2003 a dezembro de 2006. A provável etiologia da deficiência auditiva foi determinada após anamnese detalhada realizada pelo médico otorrinolaringologista; pesquisa das sorologias para toxoplasmose, rubéola, citomegalovírus, herpes, sífilis e HIV; tomografia dos ossos temporais e exames genéticos. Resultados foram diagnosticados 17 sujeitos com deficiência auditiva no período estudado. 64.7% dos casos estudados apresentaram como provável etiologia causas pré-natais, 29.4% causas peri-natais e um sujeito (5,9%) apresentou etiologia desconhecida. Das causas pré-natais, 36.4% tiveram origem genética confirmada e 36.4% etiologia presumida de hereditariedade. Foi confirmada a presença de infecções congênitas em 18.2% dos casos e um sujeito (9%) apresentou anomalia craniofacial como provável etiologia. O grau de perda auditiva mais frequente observado nos sujeitos estudados foi o profundo (47,1%). Conclusão a maior ocorrência de etiologias observada neste estudo foram as de origem pré-natal, seguida das de origem peri-natal.42242

Single Nucleotide Polymorphisms Of The Gjb2 And Gjb6 Genes Are Associated With Autosomal Recessive Nonsyndromic Hearing Loss.

Single nucleotide polymorphisms (SNPs) are important markers in many studies that link DNA sequence variations to phenotypic changes; such studies are expected to advance the understanding of human physiology and elucidate the molecular basis of diseases. The DFNB1 locus, which contains the GJB2 and GJB6 genes, plays a key role in nonsyndromic hearing loss. Previous studies have identified important mutations in this locus, but the contribution of SNPs in the genes has not yet been much investigated. The aim of this study was to investigate the association of nine polymorphisms located within the DFNB1 locus with the occurrence of autosomal recessive nonsyndromic hearing loss (ARNSHL). The SNPs rs3751385 (C/T), rs7994748 (C/T), rs7329857 (C/T), rs7987302 (G/A), rs7322538 (G/A), rs9315400 (C/T), rs877098 (C/T), rs945369 (A/C), and rs7333214 (T/G) were genotyped in 122 deaf patients and 132 healthy controls using allele-specific PCR. There were statistically significant differences between patients and controls, in terms of allelic frequencies in the SNPs rs3751385, rs7994748, rs7329857, rs7987302, rs945369, and rs7333214 (P < 0.05). No significant differences between the two groups were observed for rs7322538, rs9315400, and rs877098. Our results suggest that SNPs present in the GJB2 and GJB6 genes may have an influence on ARNSHL in humans.201531872

Single nucleotide polymorphisms of the GJB2 and GJB6 genes are associated with autosomal recessive nonsyndromic hearing loss

Single nucleotide polymorphisms (SNPs) are important markers in many studies that link DNA sequence variations to phenotypic changes; such studies are expected to advance the understanding of human physiology and elucidate the molecular basis of diseases. The DFNB1 locus, which contains the GJB2 and GJB6 genes, plays a key role in nonsyndromic hearing loss. Previous studies have identified important mutations in this locus, but the contribution of SNPs in the genes has not yet been much investigated. The aim of this study was to investigate the association of nine polymorphisms located within the DFNB1 locus with the occurrence of autosomal recessive nonsyndromic hearing loss (ARNSHL). The SNPs rs3751385 (C/T), rs7994748 (C/T), rs7329857 (C/T), rs7987302 (G/A), rs7322538 (G/A), rs9315400 (C/T), rs877098 (C/T), rs945369 (A/C), and rs7333214 (T/G) were genotyped in 122 deaf patients and 132 healthy controls using allele-specific PCR. There were statistically significant differences between patients and controls, in terms of allelic frequencies in the SNPs rs3751385, rs7994748, rs7329857, rs7987302, rs945369, and rs7333214 (P < 0.05). No significant differences between the two groups were observed for rs7322538, rs9315400, and rs877098. Our results suggest that SNPs present in the GJB2 and GJB6 genes may have an influence on ARNSHL in humans2015CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFundacao Herminio Ometto/FH

Etiological investigation of deafness in neonates screened in a universal newborn hearing screening program

Descrever os resultados da investigação etiológica da deficiência auditiva realizada em neonatos rastreados em um programa de triagem auditiva neonatal universal. Métodos estudo descritivo, transversal e prospectivo. Foram incluídos no estudo todos os neonatos diagnosticados com deficiência auditiva identificados em um programa de triagem auditiva neonatal universal no período de agosto de 2003 a dezembro de 2006. A provável etiologia da deficiência auditiva foi determinada após anamnese detalhada realizada pelo médico otorrinolaringologista; pesquisa das sorologias para toxoplasmose, rubéola, citomegalovírus, herpes, sífilis e HIV; tomografia dos ossos temporais e exames genéticos. Resultados foram diagnosticados 17 sujeitos com deficiência auditiva no período estudado. 64.7% dos casos estudados apresentaram como provável etiologia causas pré-natais, 29.4% causas peri-natais e um sujeito (5,9%) apresentou etiologia desconhecida. Das causas pré-natais, 36.4% tiveram origem genética confirmada e 36.4% etiologia presumida de hereditariedade. Foi confirmada a presença de infecções congênitas em 18.2% dos casos e um sujeito (9%) apresentou anomalia craniofacial como provável etiologia. O grau de perda auditiva mais frequente observado nos sujeitos estudados foi o profundo (47,1%). Conclusão a maior ocorrência de etiologias observada neste estudo foram as de origem pré-natal, seguida das de origem peri-natal162422429To describe the results of etiology of deaf in neonates screened in a universal newborn hearing screening program. Methods a descriptive, cross-sectional and prospective study. The study included all newborns diagnosed with hearing loss identified in a universal newborn hearing screening program from August 2003 to December 2006. The etiology of deaf was determined after detailed anamnesis performed by the otorhinolaryngologist; survey of serological tests for toxoplasmosis, rubella, cytomegalovirus, herpes, syphilis and HIV; tomography of the temporal bone and genetic tests. Results 17 neonates were diagnosed with hearing loss in the period studied. 64.7% of cases presented as probable causes prenatal etiology, 29.4% perinatal causes and one child (5.9%) had unknown etiology. Of prenatal causes, 36.4% had confirmed genetic origin and 36.4% presumed etiology of heredity. We confirmed the presence of congenital infections in 18.2% of cases and one child (9%) had craniofacial anomalies as a possible etiology. The degree of hearing loss more frequently observed in the subjects studied was the profound (47.1%). Conclusion the increased occurrence of etiologies in this study was of prenatal origin, followed by perinatal origi

Analysis of CFB (R32Q - rs641153) and CFH (rs1410996) variants as risk factors for age-related macular degeneration in a brazilian population

Age-related macular degeneration (AMD) is a progressive, mutifactorial condition that affects the central retina, and represents an important cause of blindness in the elderly population worldwide. Its pathogenesis is complex, with genetics and environmental factors playing critical roles. The genetic component of AMD has been estimated at 45% to 70%, with at least 34 genomic loci implicated in its etiology. Different variants of complement pathway-associated genes have been associated with the disease, demonstrating the importance of immune pathology and inflammation in the mechanism of AMD. The purpose of this study was to evaluate the role of the variants CFB R32Q (rs641153) and CFH (rs1410996) in the risk of development of AMD in a Brazilian population. This was a case-control study, in which 443 unrelated AMD patients and 471 controls were evaluated for the rs641153 and 451 unrelated AMD patients and 435 controls were evaluated for the rs1410996 SNPs through PCR/direct sequencing. AMD patients were diagnosed according to the International Classification System and subdivided in subgroups: dry and wet; early and advanced disease.Genotype distributions were significantly different when cases and controls were compared. When analyzing rs641153, AG/AA genotypes were more frequent in controls than in cases when compared to GG genotype (p= 0.0008), OR: 0.548 (IC95% 0.385-0.780). When comparing early versus advanced forms, GG genotype was more frequent in patients with advanced AMD (p=0.0006), OR: 1.878 (IC95% 1.081-3.262). No association was observed for the comparison of wet versus dry forms. For rs1410996, GG/AG genotypes were more frequent in cases than controls when compared to AA genotype (p=0.0296), OR: 1.462 (IC95% 1.038-2.059). For the comparison of GG versus AA genotype, OR was 2.030 (IC95% 1.375-2.996) (p=0.0002). No association was observed for the comparisons early versus advanced and dry versus wet AMD.These results are in accordance with the literature and support the role of the A variant of the CFB gene in AMD susceptibility, as a protection factor for the disease and the G variant of the CFH gene as a risk factor for the disease. To our knowledge, this is the first report of the association of these variants with AMD in Brazilians, a highly admixed population61