Genetic variation in the progesterone receptor gene and susceptibility to recurrent pregnancy loss: a case-control study.

OBJECTIVE: To investigate the association of progesterone receptor (PGR) gene variants with susceptibility to recurrent pregnancy loss (RPL). DESIGN: Retrospective case-control study. SETTING: Outpatient obstetrics and gynaecology clinics. POPULATION: Women with RPL (396), defined as three or more consecutive miscarriages of unknown aetiology, and 361 women used as controls. METHODS: PGR genotyping was performed by the allelic exclusion method (real-time polymerase chain reaction). MAIN OUTCOME MEASURES: PGR single nucleotide polymorphisms (SNPs) and the distribution of their alleles, genotypes and haplotypes. RESULTS: Higher minor allele frequencies (MAFs) for rs590688, rs10895068, and rs1942836 were seen in RPL cases than in controls, which remained significant after controlling for multiple comparisons. Significantly higher frequencies of heterozygous (1/2) rs608995, along with heterozygous (1/2) and homozygous (2/2) rs590688, rs10895068, and rs1942836 genotype carriers, were seen between RPL cases versus controls, respectively, which persisted after controlling for age, body mass index (BMI), and menarche. The increased risk of RPL associated with rs590688 and rs1942836 was dependent on the number of minor alleles, thus suggesting a 'dose-dependent' effect associated with both variants. Varied linkage disequilibrium (LD) was noted between rs590688, rs10895068, rs608995, and rs1942836 PGR variants associated with RPL. Haplotypes with an increased frequency of CGTC and reduced frequency of GGAT were noted in women with RPL, compared with controls, thereby indicating these haplotypes as RPL-susceptible and RPL-protective, respectively. This association persisted after controlling for multiple comparisons, and after adjusting for covariates. CONCLUSIONS: We have confirmed a positive association of specific PGR variants (rs590688, rs10895068, and rs1942836) and PGR haplotypes (ATGCCGTC and ATTCGGTC) with an increased risk of RPL, thereby supporting a role for PGR as an RPL candidate locus. TWEETABLE ABSTRACT: Genetic variants in progesterone receptor gene are associated with increased risk of recurrent pregnancy loss.

Endothelial nitric oxide synthase gene variants and haplotypes associated with an increased risk of idiopathic recurrent miscarriage.

We investigated the association of endothelial nitric oxide synthase (NOS3) polymorphisms rs2070744 (-786T> C), 27-bp repeat 4b/4a, rs1799983 (Glu298Asp), rs3918188 (-734C> A), and rs743507 (113G> A) with idiopathic recurrent miscarriage (IRM). This was a case-control study involving women with confirmed IRM (n = 296), and 305 age- and ethnically matched control women. NOS3 rs2070744, rs1799983, rs3918188, and rs743507 genotyping was done by TaqMan assays; NOS3 4b/4a genotyping was done by PCR-ASA. A higher frequency of -786C and 298Asp alleles was seen in IRM cases, which remained associated independently with IRM on multivariate analysis. Allele and genotype distribution of 4b/4a, rs3918188 (-734C> A) and rs743507 (113A> G) were comparable between IRM cases and control women. Taking homozygous wild-type genotype as a reference, regression analysis confirmed the association of Glu298Asp and -786T/C, and rs743507 homozygous carriers with IRM risk. Marked linkage disequilibrium was seen between tested NOS3 variants, thus allowing the construction of 5-locus [-786T> C/4b4a/Glu298Asp/-734C> A/113G> A] haplotypes. Taking the common T4bGCA haplotype as a reference, multivariate analysis confirmed the positive association of C4bTCG haplotype with IRM, after controlling for traditional covariates. Genetic variation at the NOS3 locus represents a genetic risk factor for increased susceptibility to IRM.

Association of the R67X and W303X non-sense polymorphisms in the protein Z-dependent protease inhibitor gene with idiopathic recurrent miscarriage.

Protein Z-dependent protease inhibitor (ZPI) is a 72 kDa single-chain serpin which inhibits the activated coagulation factors X and XI. Two non-sense polymorphisms of ZPI, R67X and W303X, were recently identified, and were linked with a prothrombotic state. Here, we investigated the association of the R67X (728C>T) and W303X (1438G>A) variants in the ZPI gene with recurrent spontaneous miscarriage (RSM). This was a case-control study involving a total of 288 women with a history of two consecutive or ≥3 non-consecutive pregnancy losses between 8 and 12th week of gestation, along with 304 age-matched and ethnically matched multiparous control women, with no personal or family history of pregnancy complications. The minor allele frequency of R67X (P = 0.003) and W303X (P = 0.014) were higher in RSM cases than in control women. Both single-nucleotide polymorphisms were significantly associated with RSM under the dominant genetic association model, and were in moderate linkage disequilibrium (D' = 0.412; P < 0.001). Taking the common (728)C/(1438)G haplotype as reference, multivariate analysis confirmed the positive association of (728)T/(1438)G [P = 0.043; odds ratio (OR) = 2.25; 95% confidence interval (CI) = 1.03-4.90], and (728)T/(1438)A (P = 0.022; OR = 3.93; 95% CI = 1.23-12.59) haplotypes with increased RSM risk. These differences remained significant after controlling for some covariates. These results demonstrate that both ZPI R67X and W303X non-sense variants and specific ZPI haplotypes are significantly associated with RSM.

Tumor necrosis factor-alpha polymorphisms in women with idiopathic recurrent miscarriage.

We investigated the association of tumor necrosis factor-alpha (TNFalpha) gene polymorphisms with idiopathic recurrent miscarriage (RM). TNFalpha -1031T/C, -863C/A, -857C/T, -376G/A, -308G/A, -238G/A, and +488G/A single nucleotide polymorphisms (SNPs) were investigated in 204 RM women and 248 age-matched parous women by PCR-restriction fragment length polymorphism. Significantly higher frequencies of -1031C and -376A alleles were seen in RM patients; significant differences were also noted in the distribution of -1031T/C, -376G/A, and -238G/A genotypes between case and control subjects. Haploview analysis revealed high linkage disequilibrium between -857C/T and +488G/A SNPs, but was lower between the other polymorphisms. Of the possible 52 seven-locus haplotypes constructed, 10 were common, and were included in subsequent analysis. Increased frequency of CCCGGGG and CCCGGAA haplotypes, and reduced frequency of TCCGGGG and TCCGGGA haplotypes were seen in RM patients than in controls. When the Bonferroni correction was applied, differences were significant for the CCCGGAA haplotype, which was higher (OR=4.14; 95% CI=1.84-8.95), and the TCCGGGA haplotype, which were lower among RM cases (OR=0.09; 95% CI=0.02-0.68), thereby conferring RM susceptibility and protection to these haplotypes, respectively. Multivariate analysis confirmed the positive association of only CCCGGAA haplotype with RM (P=0.010; aOR=2.03; 95% CI=1.18-4.47), after controlling for a number of covariates. These results demonstrate that the TNFalpha polymorphisms, in particular the -1031T/C variant, are significantly associated with idiopathic RM. Additional replication studies on other racial groups are needed to confirm our findings.

Detection of Chlamydia trachomatis and herpes simplex virus type 1 or 2 in cervical samples in human papilloma virus (HPV)-positive and HPV-negative women.

This study investigated whether the prevalence of human papilloma virus (HPV) in association with Chlamydia trachomatis, herpes simplex virus (HSV)-1 and/or HSV-2 was greater in high-grade than in low-grade or control cervical biopsy specimens. HPV-positive (n = 86) and HPV-negative (n = 213) women were screened for HPV, HSV and C. trachomatis by PCR. The most common HPV genotypes were HPV-16, HPV-6 and HPV-33; mixed HPV infection (n = 12) was also seen. A higher prevalence of C. trachomatis, HSV-1 and HSV-2 was found in HPV-positive samples. High-risk HPV genotypes and combined HPV + C. trachomatis or HPV + HSV-1, but not HSV-2, infections were associated with a greater risk of developing cervical carcinoma.

Methylenetetrahydrofolate reductase C677T and A1298C polymorphism and changes in homocysteine concentrations in women with idiopathic recurrent pregnancy losses.

Because they have been described as strong risk factors for idiopathic recurrent pregnancy losses (RPLs), we assessed the association between the methylenetetrahydrofolate reductase (MTHFR) single-nucleotide polymorphisms (SNPs) C677T and A1298C and hyperhomocysteinemia in Tunisian women with idiopathic RPL. Study subjects comprised 200 patients with more than three consecutive RPLs, and 200 age-matched parous control women. C677T and A1298C SNPs were analyzed by PCR-RFLP analysis, and fasting serum homocysteine was measured with ELISA. The frequency of MTHFR 677T/T (30.0 vs 7.0%) and 1298C/C (13.5 vs 4.0%) genotypes was significantly higher in patients. While it was similar among patients and controls (P = 0.095), higher homocysteine was seen with the T/T (but not 1298A/C and 1298C/C) genotype among patients and controls compared with non-T/T carriers (P < 0.05), and in patients vs controls. Higher prevalence of MTHFR 677T/T was seen in late (P < 0.05) and early-late (P < 0.001) RPL, while higher prevalence of 1298C/C genotype was seen only in early-late RPL (P < 0.001), and the prevalence of double heterozygotes was statistically not significant between patients and controls (P = 0.10; odds ratio = 2.73). Logistic regression analysis showed that, after adjusting for all variables, homozygosity for MTHFR C677T was associated with late (P < 0.001), and combined early-late (P < 0.001), while homozygosity for A1298C was associated only with combined early-late (P = 0.026), as was secondary-level education, which was associated with early (P = 0.005), late (P = 0.026) and combined early-late (P = 0.004) abortions. Homozygosity for MTHFR C677T (late and early-late) and A1298C (early-late) are risk factor for RPLs, irrespectively of total homocysteine levels.

Distribution of HLA class II (DRB1/DQB1) alleles and haplotypes among Bahraini and Lebanese Arabs.

The genetic relationship between Bahraini and Lebanese Arabs in terms of HLA class II (DRB1 and DQB1) gene and haplotype frequencies was investigated in a group of 90 Lebanese and 52 Bahraini Arabs. Subjects of both sexes were unrelated and HLA-DRB1 and DQB1 genes were genotyped using the polymerase chain reaction-sequence specific primer (PCR-SSP) technique. Analysis of the HLA-DRB1 alleles showed that the DRB1*040101 and DRB1*110101 alleles were more common among Lebanese, whereas DRB1*030101, DRB1*130701/1327, and DRB1*160101 alleles were more common among Bahrainis. Similarly, of the 7 HLA-DQB1 alleles analyzed, the presence of DQB1*0201 was higher among Bahrainis, whereas DQB1*030101 was higher among Lebanese. The DRB1*160101-DQB1*050101 (23.08%) and DRB1*030101-DQB1*0201 (21.15%) haplotypes were more frequent among Bahrainis, while the DRB1*110101-DQB1*030101 (56.67%), DRB1*040101-DQB1*0302 (28.89%) and DRB1*040101/DQB1*030101 (25.56%) haplotypes were more frequent in Lebanese subjects. Our results underline significant differences between these two populations in HLA class II distribution, and provide basic information for further studies of MHC heterogeneity among Arab-speaking countries, and as a reference for further anthropologic studies.

Identification of Chlamydia trachomatis DNA in human papillomavirus (HPV) positive women with normal and abnormal cytology.

Insofar as infection with human papillomavirus (HPV) and Chlamydia trachomatis (CT) are associated with cervical intraepithelial neoplasia (CIN), the aim of this study was to assess the correlation of HPV and CT infection in patients with normal or abnormal cytology. Endocervical samples from patients (n=121; mean age 33.7+7.0) were assessed for HPV and CT DNA by PCR. While there was no statistically significant difference between HPV-positive (n=44) and HPV-negative (n=77) patients to age pregnancies, higher proportion of smokers, patients with multiple male sex partners, or with abnormal cytology was seen in HPV-positive vs. HPV-negative women, respectively. An infection rate of CT of 21/44 was seen in HPV-positive as compared to 11/77 in HPV-negative patients. Within HPV-positive patients, there was no significant difference between CT-positive and CT-negative patients with regards to the risk factors studied. Collectively, this suggests that a causal relationship between HPV and CT infection in the development of CIN disease.

Molecular diagnosis of human papillomavirus: comparison between cervical and vaginal sampling.

BACKGROUND: Human papillomavirus (HPV) is the most significant cause of cervical cancer. In view of the number of drawbacks associated with endocervical sampling, the gold standard for HPV detection, this study examined the utility and specificity of vaginal sampling as an alternative for endocervical sampling for the routine detection of HPV. CASE STUDY: The study comprised 51 women who tested positive and 54 women who tested negative for endocervical HPV by polymerase chain reaction (PCR), confirmed by histopathology. At the time of specimen collection, both (speculum-assisted) endocervical and vaginal (no speculum) scrapings were isolated from HPV-positive and negative women, and HPV DNA was assessed by PCR using the MY09/MY11 primer system; HPV type was identified by hybridization of PCR products with type-specific biotinylated DNA probes. Each participant served as her own control. HPV was detected in vaginal and cervical scrapes from all HPV-positive but not HPV-negative women. In HPV-positive women the same HPV type was found in vaginal and endocervical scrapings (positive predictive value = 1.0). CONCLUSION: Correlation between vaginal and endocervical sampling methods was excellent in detecting the presence of HPV DNA and for identifying distinct HPV genotypes. Utilization of vaginal testing for routine HPV detection, and for the long-term follow-up of persistent HPV infection, is therefore recommended.

Detection of human papillomavirus (HPV) genotypes in cervico-vaginal scrapes of women with normal and abnormal cytology.

BACKGROUND: Certain types of human papillomavirus (HPV) are associated with cervical intraepithelial neoplasia (CIN) and invasive cervical carcinoma. The study addressed the expression and detection of HPV genotypes in cervical and vaginal specimens of women with normal and abnormal cytology by polymerase chain reaction (PCR), each woman serving as her own control. METHODS: Study participants (127) were subgrouped into CIN-positive and CIN-negative, based on cytology screening, and endocervical and vaginal scrapes were collected by a gynecologist and placed immediately in saline. HPV DNA was assessed by PCR, and HPV genotypes were determined by hybridization of PCR products with type-specific biotinylated probes. RESULTS: Of the 127 participants, 55 tested positive and 72 tested negative for HPV DNA. While there was no difference between the two groups with regards to age or to number of pregnancies, higher numbers of smokers and of women with multiple sexual partners and abnormal cytology were seen in the HPV-positive group (P < 0.001). HPV DNA was detected in the vaginal scrapes of all HPV-positive, but in none of the HPV-negative women (sensitivity and specificity = 1.0). Furthermore, the HPV genotype was the same in vaginal and endocervical specimens in all the HPV-positive women. CONCLUSION: HPV detection by PCR, using endocervical or vaginal sampling, is a sensitive and highly specific test for the identification of HPV infection, in particular in women with cytomorphologically normal cervices.

Validity of vaginal testing in detecting human papillomavirus (HPV) genotypes.

The aim of this study was to assess the validity and usefulness of vaginal scrapes in detecting cervical human papillomavirus (HPV) DNA by the polymerase chain reaction (PCR). The study group comprised 23 women tested positive and 28 women tested negative for cervical HPV DNA by PCR, and confirmed by histopathology. At the time of specimen collection, both vaginal and endocervical scrapes were taken from these women, and tested for HPV DNA by PCR, using MY09/MY11 primer system. HPV genotypes were analyzed by hybridizing PCR products with HPV type-specific biotinylated probes. HPV DNA was detected in both vaginal and cervical scrapes from the HPV-positive, but not from HPV-negative group. In the HPV-positive group, the same HPV type was found in vaginal and endocervical scrapes, giving a positive predictive value of 1.0. The results indicate that HPV types can be detected in vaginal scrapes, and recommend utilization of the less invasive vaginal testing for the routine detection of HPV DNA.