Ioanna Bouba

Association of estrogen receptor gene polymorphisms with endometriosis

OBJECTIVE To explore the association of the estrogen receptor two-allele (point) polymorphism and multiallele (microsatellite) polymorphism with endometriosis. DESIGN Case-control study. SETTING Genetics and Endoscopy Unit, Department of Obstetrics and Gynecology, Ioannina University HOSPITAL, Ioannina, Greece. PATIENT(S) Fifty-seven women with surgically and histologically diagnosed endometriosis of stages I-IV. INTERVENTION(S) Diagnostic laparoscopy. MAIN OUTCOME MEASURE(S) Frequency and distribution of the estrogen receptor gene polymorphisms. RESULT(S) There was a statistically significant difference between the patients and the controls in the frequency of the two-allele Pvu II polymorphism (0.72 vs. 0.49) and in the median repeats of the (TA)n multiallele polymorphism (15 vs. 20 repeats). In both groups, linkage was found between the fewer (TA)n repeats (range, 12-19) and the positive Pvu II polymorphism. CONCLUSION(S) The variability of the estrogen receptor gene likely contributes to the pathogenesis of endometriosis.

Interaction between the polymorphisms of the renin-angiotensin system in preeclampsia.

Preeclampsia is considered to be a multifactorial and multisystemic disorder with a genetic predisposition. Alterations in the renin-angiotensin system are considered to play a significant role in the pathogenesis of the disease. In order to investigate the possible association of the three most common polymorphisms of the renin-angiotensin system genes with preeclampsia we have examined 41 women with preeclampsia and 102 normotensive pregnant women. DNA samples were genotyped for the M235T polymorphism of the angiotensinogen gene (AGT), the insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme gene (ACE) and the A1166C polymorphism of the angiotensin II type 1 receptor gene (AT1R) by PCR. Allele and genotype frequencies of the AGT gene polymorphism differed between the two study groups. The TT genotype of the M235T polymorphism was significantly increased in women who developed preeclampsia (P<0.02). In addition, women with preeclampsia and TT genotype had more frequently the DD genotype or the 1166C allele than the control group showing a significant interaction between the genes. In conclusion, we found an association between the angiotensinogen variant 235T and preeclampsia as well as an interaction between the variant 235T and the two other genes studied.

Fragile X premutations and (TA)n estrogen receptor polymorphism in women with ovarian dysfunction.

We studied five groups of women with ovarian dysfunction for the CGG expansion in FMR1 and a (TA)n polymorphism in the estrogen receptor gene: a) poor responders to ovarian stimulation as part of in vitro fertilization (n = 13); b) women with familial premature ovarian failure (POF) (n = 7); c) sporadic cases with POF (n = 16); d) FRAXA premutation carriers with POF (n = 7); and e) FRAXA premutation carriers without POF (n = 9). FRAXA premutation was found in one woman with familial POF. A significant association of familial POF and FRAXA premutation carriers with POF having low copy of the (TA)n polymorphism as compared to controls was observed. Our preliminary data suggest a potential role of the estrogen receptor in POF, and it may influence the variable age of menopause of the FRAXA premutation carriers.

Glutathione S–Transferase Null Genotypes in Transitional Cell Bladder Cancer

Results: The GSTM1 null genotype was strongly associated with bladder cancer. The odds ratio, attributable and population attributable risks were estimated at 2.76, 0.64 and 0.40, respectively. The correlation between the GSTM1 null genotype with stage, although not statistically significant, was estimated at an odds ratio of 2.6 for invasive disease. The correlation of GSTM1 null genotype with tumor grade did not yield a statistically significant result. The GSTT1 null genotype was not statistically associated with bladder cancer.AbstractObjectives: This study was conducted (1) to examine whether the GSTM1 and GSTT1 null genotypes are risk factors for bladder cancer, and (2) to study a possible association of these genotypes with disease severity.Methods: This case–control study was undertaken over a 21–month period and included 89 newly diagnosed transitional cell bladder cancer patients and 147 controls; both patients and controls originated from a defined population (residents of the loannina region, Northwestern Greece) and were similar with regard to mean age, male to female ratio and smoking habits. The GSTM1 and GSTT1 genotypes were identified by multiplex polymerase chain reaction on peripheral blood DNA samples. Genotype frequencies among patients and controls were assessed and the association of the genotypes with tumor grade and stage at presentation were statistically evaluated by the χ2 test.Conclusion: According to our study, individuals with the GSTM1 null genotype carry a substantially higher risk for bladder carcinogenesis. The GSTM1 null genotype is not associated with more aggressive disease in terms of tumor grade, although there is a correlation between this genotype and stage of the disease.

Impact of renin-angiotensin-aldosterone system genes on the treatment response of patients with hypertension and metabolic syndrome

Objective. To evaluate the influence of clinical, biochemical and genetic markers on the response to antihypertensive treatment in patients with essential hypertension and the metabolic syndrome (MetS). Methods. Measurements of anthropometric indices, blood pressure (BP), and metabolic parameters were obtained from the medical records of 132 (77 women) newly diagnosed, untreated hypertensive patients. Renin-angiotensin-aldosterone system (RAAS) genes polymorphisms (including ACE I/D, angiotensinogen M235T, angiotensin II type 1 receptor [AT1-receptor] A1166C) were determined. Response to treatment was defined as BP less than 140/90 mmHg. Results. Patients with MetS (n=60) had higher systolic BP and pulse pressure and a more atherogenic lipid profile than patients without MetS.The frequencies of the ACE and the AT1-receptor gene polymorphisms were similar between patients with and without MetS. Response to treatment was positively associated with pulse pressure, and the presence of the C allele as well as the AC genotype of the AT1-receptor gene and inversely with age after adjustment for confounding factors. Conclusions. RAAS genes distribution does not differ between hypertensive patients with and without the MetS. Higher baseline pulse pressure levels, the presence of the C allele and/or the AC genotype may be in favour of a better response to structured antihypertensive treatment in patients with MetS. However, these findings need to be evaluated in future studies.

Gender association of the angiotensin-converting enzyme gene with ischaemic stroke

We examined the association of the NG011648 polymorphism (insertion/deletion) of the angiotensin-converting enzyme (ACE) gene with ischaemic stroke occurrence, subtype of ischaemic stroke and ischaemic stroke patients’ gender. Patients with first ever ischaemic stroke were recruited prospectively in a period of 18 months. Controls were matched with the patients for age, gender, and known risk factors for stroke. Demographic data, medical history, and vascular risk factors were collected. Genotypes were determined by polymerase chain reaction (PCR) and restriction enzyme analysis. Stroke and control groups were compared in regard to the prevalence of the NG011648 polymorphism. One hundred and seventy-six patients with ischaemic stroke and 178 controls were recruited and genotyped for NG011648 polymorphism (I/D) of the ACE gene. No significant difference in allele and genotype distributions emerged between control and patient groups, nor in the two subtype groups of lacunars and large artery atherosclerosis. After the data were stratified by gender, a low incidence of II homozygosity in female patients versus female controls (p = 0.05) and male patients (p = 0.013, Z score: -2.49) was found. Our results indicate that I/D polymorphisms may have a role in stroke onset, in respect to gender, with a possible favourable effect of II genotype in females.

Association of serum and follicular fluid SHBG levels and SHBG (TAAAA)n polymorphism with follicle size in women undergoing ovarian stimulation

Objective. Sex hormone-binding globulin (SHBG) is the main transport protein of sex steroids. Recently, it has been found to be produced by granulosa lutein cells, suggesting a local role of SHBG in the ovary. The aim of this study was to investigate whether serum and follicular fluid SHBG levels and SHBG (TAAAA)n polymorphism are related to follicle size and pregnancy rate in women undergoing in vitro fertilisation. Methods. The study population consisted of 154 women with tubal and/or male-factor infertility undergoing IVF/ICSI and follicular fluid with oocytes from small (diameter ≤12 mm) and large (diameter ≥18 mm) follicles were studied. Genotyping of SHBG (TAAAA)n polymorphism was performed in peripheral blood samples. Serum and follicular fluids were used for hormones determination. Results. Women with short allele genotypes (with less than 8 TAAAA repeats) had higher number of small follicles compared to women with long allele genotypes (5.6 ± 3.9 vs. 3.5 ± 3.2 small follicles, p < 0.003). Follicular fluid SHBG levels correlated positively with serum SHBG levels (p < 0.001) and with the total number of follicles (p < 0.02). Furthermore, small follicles had higher follicular fluid SHBG concentration compared to large follicles (102.9 ± 35.0 nmol/l vs. 85.85 ± 34.88 nmol/l, p < 0.028). Conclusion. SHBG levels and the SHBG (TAAAA)n polymorphism are associated with follicle size.

Non-Invasive Prenatal Detection of Paternal Origin Hb Lepore in a Male Fetus at the 7th Week of Gestation

Objective: To perform a reliable non-invasive prenatal detection of the Hb Lepore paternal mutation and determine the fetal gender in the first trimester of pregnancy. Methods: DNAwas extracted from a serum sample obtained from a pregnant womanat the mid first trimester of gestation. Hb Lepore-specific, mutant and normal, primers as well as Y-chromosome-specific STSs were used to carry out the analysis. Results: Paternal Hb Lepore and the DYS14 and DYZ1 gene-specific sequences were detected in the serum sample obtained at the 7th week of pregnancy. None of the above sequences was detectable in the maternal peripheral blood cell DNA. Conclusion: Conventional polymerase chain reaction analysis of cell-free fetal DNA can be used to determinefetal gender and paternal Hb Lepore as early as the 7th week of pregnancy.

Novel PKD1 deletions and missense variants in a cohort of Hellenic polycystic kidney disease families.

The autosomal dominant form of polycystic kidney disease is a very frequent genetically heterogeneous inherited condition affecting approximately 1 : 1000 individuals of the Caucasian population. The main symptom is the formation of fluid-filled cysts in the kidneys, which grow progressively in size and number with age, and leading to end-stage renal failure in approximately 50% of patients by age 60. About 85% of cases are caused by mutations in the PKD1 gene on chromosome 16p13.3, which encodes for polycystin-1, a membranous glycoprotein with 4302 amino acids and multiple domains. Mutation detection is still a challenge owing to various sequence characteristics that prevent easy PCR amplification and sequencing. Here we attempted a systematic screening of part of the duplicated region of the gene in a large cohort of 53 Hellenic families with the use of single-strand conformation polymorphism analysis of exons 16–34. Our analysis revealed eight most probably disease causing mutations, five deletions and three single amino acid substitutions, in the REJ domain of the protein. In one family, a 3-bp and an 8-bp deletion in exons 20 and 21 respectively, were co-inherited on the same PKD1 chromosome, causing disease in the mother and three sons. Interestingly we did not find any termination codon defects, so common in the unique part of the PKD1 gene. In the same cohort we identified 11 polymorphic sequence variants, four of which resulted in amino acid variations. This supports the notion that the PKD1 gene may be prone to mutagenesis, justifying the relatively high prevalence of polycystic kidney disease.

Association of the A1330V and V667M polymorphisms of LRP5 with bone mineral density in Greek peri- and postmenopausal women

UNLABELLED Wnt signaling through low-density lipoprotein receptor-related protein 5 (LRP5) is an important determinant of bone mass regulation. OBJECTIVE To explore the influence of two LRP5 single nucleotide polymorphisms (SNPs) A1330V and V667M on bone mineral density (BMD) and serum levels of osteoprotegerin (OPG), receptor activator of nuclear factor-κB ligand (RANKL) and bone metabolic markers in a Greek female population. STUDY DESIGN Two hundred and nine postmenopausal and twelve perimenopausal women aged 40-63 years were enrolled. All participants underwent spinal BMD evaluation. Genotyping of A1330V and V667M polymorphisms was performed by real-time polymerase chain reaction. Levels of OPG, soluble RANKL (sRANKL) and bone metabolic markers were measured. RESULTS As regards A1330V SNP, women carrying CT/TT genotypes had lower spinal BMD than women with CC (p<0.0001). Regarding V667M SNP, spinal BMD was lower in women with GA/AA than in women with GG genotypes (p<0.0001). These differences remained significant after adjustment for age, years since menopause and body mass index. The A1330V and V667M polymorphisms were in strong linkage disequilibrium. A significant interaction between A1330V and V667M SNPs on spinal BMD was revealed. The haplotype with both risk alleles of the two SNPs (AT) conferred more risk for low BMD than the haplotypes with one risk allele (GT or AC) or the haplotype-reference (GC) (p=0.046, p=0.045, and p=0.010, respectively). No effect was observed on circulating OPG, sRANKL levels and bone metabolic markers. CONCLUSIONS These findings demonstrate that the A1330V and V667M polymorphisms are associated with low BMD in peri- and postmenopausal Greek women.