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The article presents a study that determines the distribution of fragile X mental retardation 1 (FMR1) alleles and the prevalence of permutation (PM) and full mutation (FM) of the gene in Korean women. It describes the method of the study that uses polymerase chain reaction and Southern blot on 5829 of reproductive age. It notes the result of the study which indicates the carrier frequency in Korean women of reproductive age, which is lower than the Caucasians.

Abstract Objective: Mutations in the GJB2 gene are a major cause of hereditary hearing loss. However, only a few studies have investigated carrier frequencies of GJB2 mutations in the general population. The aim of this study was to estimate the carrier frequencies of three GJB2 mutations, including 235delC, V37I, and G45E, in the general Korean population. Design: A standard questionnaire of self-reported hearing loss was used to identify and recruit subjects. Screening for three mutations was performed using an allele-specific polymerase chain reaction (PCR), PCR-restriction fragment length polymorphism, and direct DNA sequencing. Study sample: A total of 1256 unrelated healthy individuals were analysed in the present study. Results: Of the 1256 individuals, 24 had GJB2 mutations; 11 were found to be heterozygous for 235delC, 11 were heterozygous and one was homozygous for V37I, and one was heterozygous for G45E. One individual had a compound heterozygous mutation of 235delC/V37I. The allele frequencies of 235delC, V37I, and G45E mutations were 0.44%, 0.52%, and 0.04%, respectively. The carrier frequency of either the 235delC or V37I mutation was estimated to be 0.88% with 95% binomial CI, 0.44-1.56. Conclusions: These results will facilitate diagnosis of, and genetic counseling for, hearing loss in Koreans. Sumario Objetivo: Las mutaciones del gene GJB2 son una causa muy importante de pérdidas auditivas hereditarias. No obstante, solamente pocos estudios han investigado las frecuencias portadoras de las mutaciones del GJB2 en la población general. El objetivo de este estudio fue estimar las frecuencias portadoras de tres mutaciones del GJB2, incluyendo la 235delC, V37I y G45E, en la población general de Corea. Diseño: Se utilizó un cuestionario estándar de pérdida auditiva auto-reportada para identificar y reclutar sujetos. El tamiz de las tres mutaciones se realizó usando una reacción en cadena de la polimerasa alelo-específica (PCR), el polimorfismo de los fragmentos de restricción PCR y la secuenciación directa de DNA. Muestra de estudio: Se analizaron en este estudio 1,256 individuos sanos, no relacionados, (sanos en este estudio). Resultados: De los 1,256 individuos, 24 tenían mutaciones del GJB2; 11 se encontraron como heterocigóticos para el 235delC, 11 fueron heterocig ticos y uno fue homocigótico para V37I y uno fue heterocigótico para G45E. Un individuo tenía una mutación heterocigótica compuesta del 235delC/V37I. Las frecuencias de las mutaciones del alelo de 235delC, V37I, y G45E fueron del 0.44%, 0.52%, y 0.04%, respectivamente. La frecuencia portadora de las mutaciones tanto del 235delC como del V37I se estimó en 0.88%, con CI binomial del 95% de 0.44-1.56. Conclusiones: Estos resultados facilitarán el diagnóstico y el asesoramiento genético en casos de pérdida auditiva en la población de Corea. [ABSTRACT FROM AUTHOR]

Background: Preeclampsia is a major cause of maternal and perinatal mortality and morbidity. The etiology of preeclampsia remains unclear. Recently, it was shown that misregulation of fms-like tyrosine kinase-1 (Flt-1) in the peripheral blood mononuclear cells of pregnant women results in over-expression of the soluble splice variant of Flt-1, sFlt-1, producing an additional (extra-placental) source of sFlt-1 that can contribute to the etiology of preeclampsia. The aim of this study was to investigate the relationship between preeclampsia and a dinucleotide (threonine-glycine; TG)n repeat polymorphism in the 3' non-coding region of the Flt-1 gene., Methods: The number of the d(TG)n repeats was analyzed in 170 patients with preeclampsia and in 202 normotensive pregnancies. The region containing the dinucleotide repeat polymorphism of the Flt-1 gene was amplified by polymerase chain reaction (PCR) from the DNA samples and was analyzed by direct PCR sequencing., Results: We found 10 alleles of the dinucleotide repeat polymorphism and designated these as allele*12 (A1) through allele*23 (A12) according to the number of the TG repeats, from 12 to 23. The frequency of the 14-repeat allele (A3) was most abundant (63.82% in preeclampsia and 69.06% in controls), followed by the 21-repeat allele (A10; 28.53% in preeclampsia and 23.76% in controls). There was no significant difference in the allele frequency between patients with preeclampsia and normal controls. The most common genotype in preeclamptic and normotensive pregnancies was heterozygous (TG)14/(TG)21 (41.76%) and homozygous (TG)14/(TG)14 (45.05%), respectively. However, the genotype frequencies were not significantly different between preeclamptic patients and controls., Conclusion: This is the first study to characterize the dinucleotide repeat polymorphism of the Flt-1 gene in patients with preeclampsia. We found no differences in the allele or genotype frequencies between patients with preeclampsia and normal pregnancies. Although limited by a relatively small sample size, our study suggests that the d(TG)n repeat polymorphism of the Flt-1 gene is not associated with the development of preeclampsia in Korean pregnant women.