Determination of the carrier frequencies of selected GJB2 mutations in the Korean population.

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.

Genetic polymorphism of catechol-O-methyltransferase and cytochrome P450c17α in preeclampsia.

OBJECTIVE: Catechol-O-methyltransferase (COMT) and cytochrome P450c17α (CYP17A1) are key enzymes involved in the metabolism of steroid hormones; genetic polymorphisms in these genes affect enzyme activity. Recently, functional polymorphisms in the COMT and CYP17A1 genes have been suggested as a susceptible marker for intrauterine fetal growth restriction, a typical complication of preeclampsia. Moreover, a close association between COMT and preeclampsia was reported. We therefore investigated the relationships between COMT and CYP17A1 polymorphisms and the risk of preeclampsia. METHODS: A total of 164 preeclamptic women and 182 normotensive women were enrolled. COMT (Val158Met) and CYP17A1 (-34T/C) polymorphisms were genotyped by quantitative fluorescent-polymerase chain reaction. Multiple logistic regression analysis was used to estimate the risks of preeclampsia according to genotypes. RESULTS: The adjusted odds ratios (adjOR) for the risks of preeclampsia, severe preeclampsia and preeclampsia for small-for-gestational-age (SGA) infants were 1.97 [95% confidence interval (CI): 1.02-3.83], 3.29 (95% CI: 1.60-6.77), and 4.05 (95% CI: 1.78-9.22), respectively, in women homozygous for the variant COMT allele. No significant differences were observed between the two groups with respect to CYP17A1 polymorphisms, indicating that variants of this gene have no effects on preeclampsia. The highest risks of preeclampsia were found among women with homozygous variant genotypes of both genes [adjOR (95% CI): 4.58 (1.92-22.81)]. Moreover, the adjOR for preeclamptic complications in those women was 5.09 (95% CI: 1.93-27.88) for severe preeclampsia and 15.65 (95% CI: 3.19-76.82) for SGA preeclampsia. CONCLUSION: These findings suggest that homozygosity for the variant allele of the maternal COMT gene may increase susceptibility to preeclampsia.

Ovarian leiomyoma as a potential cause of compromised fertility.

OBJECTIVE: To analyze cases of ovarian leiomyomas and to discuss the proper surgical management. DESIGN: A case series and discussion. SETTING: General university hospital and healthcare center. PATIENT(S): Nine patients who were diagnosed with ovarian leiomyomas after surgery between 1993 and 2009. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): A preoperative diagnosis that was matched to the postoperative diagnosis and the type of surgery. RESULT(S): In all cases, ovarian leiomyoma was misdiagnosed preoperatively as pedunculated uterine myoma, ovarian fibroma, or even ovarian endometrioma. Seven (77.8%) of the nine patients underwent a salpingo-oophorectomy or an oophorectomy with or without hysterectomy, and only two (22.2%) patients were submitted to an ovary-preserving surgery (i.e., a cystectomy or ovarian wedge resection). CONCLUSION(S): Because of their extreme rarity, ovarian leiomyomas are seldom suspected intraoperatively or preoperatively. However, most of these tumors appear at reproductive age and have a benign nature, similar to uterine myomas. Therefore, surgeons should perform ovary-preserving management, especially in young patients.