Polymorphisms of the Nos3 gene and unexplained late intrauterine fetal death

Genetic association studies of endothelial nitric oxide synthase gene polymorphisms in women with unexplained recurrent pregnancy loss: a systematic and meta-analysis

Recurrent pregnancy loss (RPL) is a multifactorial disorder, both genetic and environmental factors contribute to the development of RPL. Recently, the association between endothelial nitric oxide synthase (eNOS) gene polymorphisms and unexplained recurrent pregnancy loss (URPL) has been reported, and the results were inconsistent. Hence, we performed the meta-analysis to drive a more precise estimation of association between eNOS polymorphisms and URPL. Odds ratio (OR) and its 95% confidence interval were calculated under co-dominant (AA vs. BB, TT vs. GG) and additive (A vs. B, T vs. G) genetic models. Studies of eNOS intron 4 VNTR and Glu298Asp were separated by ethnicities. 13 studies included 1,769 URPL cases and 1,376 healthy controls on eNOS intron 4 VNTR polymorphism, and 11 studies were involved in Glu298Asp polymorphism with 1,498 URPL cases and 1,123 healthy controls. The integrated results showed that eNOS Glu298Asp polymorphism was associated with URPL [ORs were 1.91 (1.42-2.56), P < 0.001; 1.67 (1.36-2.04), P < 0.001, respectively]. When analyses were separated by ethnic subgroups, the association between eNOS Glu298Asp polymorphism and URPL was only observed in East Asians [OR = 1.88 (1.52-2.33), P < 0.001 under additive model], and there was no association between eNOS intron 4 VNTR polymorphism and URPL in Caucasians and East Asians. The results indicated a significant association between eNOS Glu298Asp polymorphism and URPL in East Asians. No association was observed between eNOS intron 4 VNTR polymorphism and URPL in Caucasians and East Asians.

Single-nucleotide polymorphisms in genes involved in placental function and unexplained stillbirth

OBJECTIVE

The purpose of this study was to evaluate the association between unexplained stillbirth (SB) and single-nucleotide polymorphisms (SNPs) in genes involved in placental function using a well-characterized cohort.

STUDY DESIGN

Placentas were obtained from 50 unexplained SB and 46 live birth controls. Classification of stillbirth was by Wigglesworth criteria. SBs were stratified by weight: appropriate (AGA-SB) and small for gestational age (SGA-SB, less than the 10th percentile) and gestational age: before 32 and after 32 weeks. Placental DNA was extracted and various SNPs in the endothelial nitric oxide synthase (eNOS), Klotho, hypoxic inducible factor-1α, and and tumor necrosis factor-α genes were evaluated.

RESULTS

None of the SNPs were associated with SB overall. Significantly different genotype distribution emerged for eNOS-SNP rs1800783 when comparing AGA-SB with SGA-SB and control (P = .004). Its allele-A was more frequent in AGA-SB compared with both controls (P = .03) and SGA-SB (P = .001). No differences were seen accordingly to gestational age.

CONCLUSION

Unexplained stillbirth in the setting of adequate growth is associated with carrier of allele A of rs1800783 eNOS gene in the placenta.

Vascular endothelial growth factor gene polymorphisms in Korean patients with premature ovarian failure

OBJECTIVE

To study the association of vascular endothelial growth factor (VEGF) polymorphisms (-2578C>A, -1154G>A, -634G>C, and 936C>T) with premature ovarian failure (POF) in Korean patients.

STUDY DESIGN

Prospective case-control study. One hundred and thirty five patients with POF and confirmed serum follicle-stimulating hormone levels of >40IU/L before the age of 40 years and 120 healthy controls with at least one live birth, regular menstrual cycles, and karyotype 46, XX.

RESULTS

POF patients exhibited significantly different frequencies of the VEGF -1154GA genotype (odds ratio [OR], 2.002; 95% confidence interval [CI], 1.116-3.592; P=0.019), and -2578CA+AA/-1154GA+AA combination genotype (OR, 1.805; 95% CI, 1.013-3.217; P=0.044) compared to the control group. The frequency of the -2578A/-1154A haplotype (OR, 1.647; 95% CI, 1.017-2.677; P=0.041) was significantly higher in the POF group than in the control group.

CONCLUSION

The VEGF -1154G>A mutation, -2578CA+AA/-1154GA+AA combination genotype, and -2578A/-1154A haplotype are significantly associated with POF in Korean women.