RESUMO
Hemophilia A is an X-linked, inherited, bleeding disorder caused by the partial or total inactivity of the coagulation factor VIII (FVIII). Due to difficulties in the direct recognition of the disease-associated mutation in the F8 gene, indirect diagnosis using polymorphic markers located inside or close to the gene is used as an alternative for determining the segregation of the mutant gene within families and thus for detecting carrier individuals and/or assisting in prenatal diagnosis. This study characterizes the allelic and haplotype frequencies, genetic diversity, population differentiation and linkage disequilibrium of five microsatellites (F8Int1, F8Int13, F8Int22, F8Int25.3 and IKBKG) in samples of healthy individuals from São Paulo, Rio Grande do Sul and Pernambuco and of patients from São Paulo with haemophilia A to determine the degree of informativeness of these microsatellites for diagnostic purposes. The interpopulational diversity parameters highlight the differences among the analyzed population samples. Regional differences in allelic frequencies must be taken into account when conducting indirect diagnosis of haemophilia A. With the exception of IKBKG, all of the microsatellites presented high heterozygosity levels. Using the markers described, diagnosis was possible in 10 of 11 families. The F8Int22, F8Int1, F8Int13, F8Int25.3 and IKBKG microsatellites were informative in seven, six, five and two of the cases, respectively, demonstrating the effectiveness of using these microsatellites in prenatal diagnosis and in carrier identification in the Brazilian population.
Assuntos
Triagem de Portadores Genéticos/métodos , Hemofilia A/genética , Repetições de Microssatélites/genética , Alelos , Brasil , Análise Mutacional de DNA , Feminino , Frequência do Gene , Marcadores Genéticos/genética , Genótipo , Haplótipos/genética , Hemofilia A/diagnóstico , Humanos , Desequilíbrio de Ligação , Masculino , Linhagem , Diagnóstico Pré-Natal/métodosRESUMO
The objective of this study was to show the association patterns among seven types of dental anomalies (second pre-molar agenesis, upper side incisive reduced in size, lower first molar infra-ochlesis, enamel hypoplasia, first molar ectopic eruption, supra numerous teeth and upper canine ectopic eruption) in a population sample without dental treatment ranging in age from 7 to 14. A total of 172 patients were attended and underwent the clinical examination at the Clínica Infantil da Fundação Educacional de Barretas. Eleven patients from this total were selected according to a first dental anomaly diagnosis and submitted to panoramic radiography. A significant association (p<0.05) was detected among six pairs of anomalies (second pre-molar agenesis x first pre-molar ectopic eruption; second pre-molar agenesis x lower first molar infra-ochlesis; second pre-molar agenesis x upper side incisive reduced in size; supra numerous teeth x reduced size upper side incisive; first pre-molar ectopic eruption x enamel hypoplasia; lower first molar infra-ochlesis x upper side incisive reduced in size) suggesting a common genetic origin for these conditions. The association was not significant in only one case where there was anomaly sharing by the patients. The existence of an anomaly is clinically relevant for early diagnosis of a possible association and an anomaly can indicate an increased risk of other anomalies.
El objetivo de este estudio fue mostrar los patrones asociación entre siete tipos de anomalías dentales (agenesia del segundo premolar, incisivo lateral superior en tamaño reducido, infra-oclesis del primer molar inferior, hipoplasia del esmalte, erupción ectópica del primer molar, dientes supernumerarios y erupción ectópica de caninos superiores) en una muestra de población sin tratamiento dental, de edades comprendidas entre los 7 a 14 años. Un total de 172 pacientes fueron atendidos y se les realizó el examen clínico en la Clínica Infantil da Fundación Educacional de Barretos. Once pacientes de el total fueron seleccionados de acuerdo con un primer diagnóstico de anomalías dentales y presentado en la radiografía panorámica. Se observó una asociación significativa (p <0,05) entre los seis pares de anomalías (agenesia de segundo premolar x erupción ectópica del primer molar; agenesia del segundo premolar x infra-oclesis del primer molar inferior; agenesia del segundo premolar x incisivo lateral superior en tamaño reducido; dientes supernumerarios x incisivo lateral superior en tamaño reducido; erupción ectópica del primer molar x hipoplasia de esmalte; infra-oclesis del primer molar inferior x incisivo lateral superior en tamaño reducido), sugiriendo un origen genético común para estas condiciones. La asociación no fue significativa en un sólo caso donde hubo anomalías compartidas por los pacientes. La existencia de una anomalía es clínicamente relevante para el diagnóstico precoz de una posible asociación y una anomalía puede indicar un mayor riesgo de otras anomalías.
Assuntos
Humanos , Masculino , Adolescente , Feminino , Criança , Anormalidades Dentárias/epidemiologia , Anormalidades Dentárias/etiologia , Anormalidades Dentárias/genética , Brasil/epidemiologiaRESUMO
The human leukocyte antigen-G (HLA-G) gene plays an important role in pregnancy and is related to negative signals for natural killer cells and T lymphocytes. Herein a new HLA-G allele (HLA-G*010111) is described in the Brazilian population--one of the most heterogeneous populations in the world. The new allele is associated with the 14-bp deletion at exon 8 and is similar to the HLA-G*01010105 allele, except for a C to G transversion at codon 117 in exon 3.