Elif Yesilada

Genotoxicity Testing of Four Textile Dyes in Two Crosses of Drosophila Using Wing Somatic Mutation and Recombination Test

In this study, four textile dyes, namely Astrazon Yellow, Red, Blue, and Black, were tested for their genotoxic effects in the wing cells of Drosophila melanogaster. Two crosses were used, the standard cross (ST) and the improved high-bioactivation cross (HB), the latter being characterized by increased sensitivity to the genotoxic effects of promutagens and procarcinogens. Three-day-old larvae were exposed to different concentrations of dyes. Commonly known mutagens were applied as positive controls. All concentrations of textile dyes, ethyl methanesulfonate (EMS), and urethane caused a decrease in survival proportional to concentration used. EMS and urethane caused an increase in the number of all types of spots in both standard and high-bioactivation crosses. Compared to ST crosses, the number of induced spots in the HB cross treated with urethane was considerably high. Treatment of the standard and the high-bioactivation crosses with textile dyes gave positive results, apparent from increase in the frequency of the small single spots. Yellow and red dyes also increased the number of large single spots in both crosses, whereas the twin spots were positive only at the highest dose of yellow dye. All these results indicate that D. melanogaster wing spot test can be recommended as a suitable in vivo test for the determination of genotoxicity of textile dyes.

Micronucleus frequency in peripheral blood lymphocytes and exfoliated buccal cells of untreated cancer patients

Some genetic diseases may increase the cellular instability. Since most human tumors have some genetic base, this study was undertaken for the genetic instability in cancer patients by micronucleus analysis, a mutation-screening test, which is more practical and economic technique than metaphase analysis carried out for chromosomal aberrations. Genetic changes were assessed in untreated cancer patients (lung, stomach and colon cancer) by different genotoxical screening methods: the cytokinesis-block micronucleus test and the buccal mucosa cell micronucleus test. The evaluation of micronuclei number in peripheral blood lymphocytes and buccal cells showed genomic instability in somatic cells. There was a significant increase in the number of micronuclei in cancer patients prior to the initiation of chemotherapy, and/or radiotherapy compared with healthy human subjects. Furthermore, there was no significant difference between smokers and non-smoking groups or male and female groups. These results suggest that cancer in humans is characterized by an increase of chromosomal damage and thus, the micronucleus assay carried out here may be useful in routine cytogenetic studies of cancer.

Angiotensin-converting enzyme gene polymorphism and risk of insulin resistance in PCOS

The aim of this study was to establish the frequency of angiotensin-converting enzyme (ACE) insertion (I) or deletion (D) gene polymorphism in women with polycystic ovary syndrome (PCOS) and to examine the association of this polymorphism with insulin resistance. A total of 32 women with PCOS and 31 healthy, age- and body mass index-matched controls were studied. Serum lipids, fasting glucose, insulin and other hormones concentrations were measured. Homeostasis model assessment was used to estimate insulin resistance (HOMA-IR). DNA was extracted from peripheral blood leukocytes and genotyping of ACE I/D polymorphism was carried out by polymerase chain reaction. ACE genotypes were distributed as follows: DD was present in 16 (50%), ID in 12 (37.5%) and II in four (12.5%) PCOS patients, and DD in seven (22.6%), ID in 20 (64.5%) and II in four (12.9%) of healthy subjects. The frequency of D and I alleles were found in 69% and 31% of the PCOS group and 55% and 45% in the control group, respectively. There were no significant differences regarding the genotypic distribution and allelic frequency between the groups. However the ACE DD genotype was significantly associated with serum insulin concentrations and HOMA-IR measurement (both P=0.005). ACE DD genotype is associated with an increased insulin resistance in women with PCOS.

Prevalence of known mutations and a novel missense mutation (M694K) in the MEFV gene in a population from the Eastern Anatolia Region of Turkey.

Familial Mediterranean fever (FMF) is an autosomal recessive disorder characterized by recurrent attacks of fever and serositis. Mutations in the Mediterranean fever gene (MEFV) localized on the short arm of chromosome 16 cause FMF. Over 90 MEFV missense/nonsense mutations have been identified so far in FMF patients, mostly in the 10th exon of the gene. In this study, the molecular test results of 891 patients identified as having FMF clinical symptoms referred to Molecular Genetics Laboratory of the Department of Medical Biology and Genetics, Faculty of Medicine, Inonu University, Malatya/Turkey were retrospectively evaluated. Patients were referred by their physicians for MEFV mutation detection. The DNA fragments including hot spots within the coding sequences of the MEFV gene were amplified by PCR using genomic DNA and analyzed by pyrosequencing technique. Of the 891 patients investigated, 420 (47.13%) had at least one mutation. The most frequent mutation was E148Q, followed by M694V, M680I (G/C), P369S, V726A, R761H, A744S, M694I, K695R and F479L mutations. In addition, a novel missense mutation (M694K) was reported in seven members of a family in the course of mutation screening of patients.

Determination of risk factors in obese and non-obese patients with coronary artery disease.

Objective — Obesity is a complex multifactorial chronic disorder recently classified by the American Heart Association (AHA) as a modifiable risk factor for coronary artery disease (CAD). This study was designed to assess conventional and novel risk factors in obese and non-obese patients with CAD. Methods and results —This study evaluates the association between conventional and novel coronary risk factors and CAD in obese and non-obese patients by using multivariate stepwise logistic regression analysis.The obese CAD group was identified by the following predictors of CAD: age, sex, hypertension, diabetes mellitus, smoking, family history of CAD, low level of HDL cholesterol, high LDL cholesterol, high C-reactive protein, high homocysteine. In a non-obese CAD group, the identified predictors of CAD were age, sex, hypertension, smoking, family history of CAD, levels of high C-reactive protein, and high homocysteine. Hypertension was found to be the strongest predictor for both obese (OR: 39.91, 95% confidence intervals (CI): 5.51-280.3, p < 0.001) and non-obese (OR: 14.39, 95% CI: 4.4-25.8, p < 0.001) patients with CAD. Conclusions — From our data, we conclude that hypertension appears to be the strongest independent predictor of CAD regardless of body mass index (BMI).

Association of eNOS Gene Polymorphisms G894T and T-786C with Risk of Hepatorenal Syndrome

Background. There are no studies investigating the relationship between endothelial nitric oxide synthase (eNOS) gene polymorphisms and hepatorenal syndrome (HRS). Aim. The purpose of this study is to elucidate whether eNOS gene polymorphisms (G894T and T-786C) play a role in the development of type-2 HRS. Methods. This study was carried out in a group of 92 patients with cirrhosis (44 patients with type-2 HRS and 48 without HRS) and 50 healthy controls. Polymorphisms were determined by polymerase chain reaction (PCR) and melting curve analysis. Results. We did not find any significant difference in allele and genotype distributions of the eNOS -T-786C polymorphism among the groups (p = 0.440). However, the frequency of GT (40.9%) and TT (13.6%) genotypes and mutant allele T (34.1%) for the eNOS G894T polymorphism were significantly higher (p < 0.001 and p < 0.001, resp.) in the HRS group than in both the stable cirrhosis (14.6%, 4.2%, and 11.5%, resp.) and the control (22.0%, 2.0%, and 13.0%, resp.) groups. Conclusion. The occurrence of mutant genotypes (GT/TT) and mutant allele T in eNOS -G894T polymorphisms should be considered as a potential risk factor in cirrhotic patients with HRS.

The Investigation of Polymorphisms in DNA Repair Genes (XRCC1, APE1 and XPD) in Women with Polycystic Ovary Syndrome

Background: PCOS was reported to arise from the interaction of genetic and environmental factors. Some studies reported that women with PCOS have DNA damage and chromosome breakage. Such studies bring to mind the genes that are involved in DNA repairing. At present, several DNA repair genes and, as products of these genes, certain polymorphisms that alter the activity of proteins are known in the literature. The aim of this dissertation is to study the genomic instability that have been reported in PCOS cases along with the relationship between XRCC1 Arg194Trp, XRCC1 Arg399Gln, APE1 Asp148Glu, and XPD Lys751Gln polymorphisms in order to contribute to the pathogenesis of PCOS. Methods: Polymorphisms in DNA repair genes have been associated with the increased risk of various diseases and could also be related to the etiology of PCOS. Therefore, we conducted a study including 114 women with PCOS and 91 controls. These polymorphisms were determined by quantitative real time PCR and melting curve analysis using LightCycler. Results: Comparing the control groups at the end of the study, the results have not shown any statistically significant difference as far as XRCC1 Arg194Trp, XRCC1 Arg399Gln, and XPD Lys751Gln polymorphisms are concerned. However, there were notable differences between the groups in terms of APE1 Asp148Glu polymorphism. Associated with this condition, it has been noted that both mutant allele (Glu) frequency (37.72 % in the study group; 19.23% in the control group, p=0.0001) and homozygous mutant genotype (Glu/Glu) frequency (%12.28 in the study group; %6.60 in the control group, p=0.015) have been higher in the study group.

Presence of a D8/17 B lymphocyte marker and HLA-DR subgroups in patients with rheumatic heart disease.

OBJECTIVE The aim of our study was to investigate the association of HLA antigens and a non-HLA protein D8/17 with rheumatic heart disease and its pattern of cardiac involvement. METHODS This cross- sectional observational study included 35 children and 12 adult patients who have rheumatic heart disease and 35 healthy children and 12 healthy adult controls. After physical examination, all patients and control group members were evaluated with 2D and color-coded echocardiography. B- lymphocyte D8/17 expression was tested by a flow cytometry assay. HLA genotyping was performed using polymerase chain reaction sequence-specific primers. In statistical analysis, Chi-square, unpaired t and Mann-Whitney U tests were used for comparison groups. RESULTS The percentage of the D8/17-expressing B lymphocytes of the patient group was significantly higher than of the control group (77.3±15.6% vs. 67.7±20.0%, p=0.013). When compared with the control group, the HLA DRB5 (38.6% vs. 13.6%, p=0.007) and HLA DRB1*15 (31.8% vs. 9.0%, p=0.008) expression levels of the patient group were significantly higher and the DRB4 expression of the patient group was significantly lower (29.5% vs. 50.0%, p=0.049). CONCLUSION Our findings support the association between HLA Class 2 subgroups and rheumatic heart disease, and an association between D8/17 expression and rheumatic heart disease. Further studies including higher number of patients and control group members should be performed for the confirmation of our results.