Genetic association of the BsmI variant of vitamin D receptor gene with risk of morbid obesity.

OBJECTIVE: The aim of this study was to evaluate the vitamin D receptor (VDR) BsmI variant in morbidly obese patients compared with healthy normal controls. METHODS: The study included 103 patients with morbid obesity and 120 healthy individuals serving as normal controls. The DNA samples obtained from blood were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. The gender, age, smoking status, triglycerides, total cholesterol, insulin, mean body mass index, and frequency of allele and genotype of the BsmI variant in the VDR gene in morbidly obese patients were evaluated. RESULTS: The body mass index of the patients was 47.14 ± 7.19. The VDR B/B, B/b, and b/b genotype frequencies were 27.2% versus 28.3%; 54.4% versus 50%; and 18.4% versus 21.7% in the morbidly obese patients and the control group, respectively. There was no statistically significant difference between patients and control subjects in the genotype and allele distribution of the VDR BsmI variant (p>0.05). Both patients and control genotype frequencies are consistent with Hardy-Weinberg equilibrium. CONCLUSION: The BsmI variant in the VDR gene may not seem to predispose to morbid obesity in our study population. Further studies with a larger number of subjects are needed to make a more precise evaluation of this relationship.

The role of the progesterone receptor PROGINS variant in the development of fibromyalgia syndrome and its psychological findings.

Fibromyalgia syndrome (FMS), a chronic pain disorder of unknown etiology, is more common in women. This suggests that biological sex is important. Therefore, we performed an analysis to determine whether the progesterone receptor (P GR) gene Alu insertion (named P ROGINS) variant is associated with an increased risk of FMS in the Turkish population. A total of 288 subjects, including 138 patients diagnosed with FMS according to the 2016 American College of Rheumatology criteria and 150 healthy subjects, were evaluated. Genotyping of the P GR P ROGINS variant was determined by polymerase chain reaction (P CR) analysis. The results of the analyses were evaluated for statistical significance. There were no subjects in the control group carrying the T2 allele. The P GR P ROGINS T1/T2 genotype was more prevalent in both all patients and female patients compared to all controls and female controls (p = 0.001, p = 0.003, respectively). A statistically significant relationship was observed in both all patients and female patients when compared to the control group according to T1/T1 vs. T1/T2+T2/T2 (p < 0.000, p < 0.001, respectively). The current study suggests that the P GR Alu insertion variant T2 allele might influence FMS susceptibility in the Turkish population. Large-sample sizes and studies of different ethnicities are required to further evaluate the association between this variant and FMS.

Evaluation of the association COMT Val158Met variant and childhood trauma on aggression in Turkish SCZ patients.

Childhood trauma is a serious form of stress that makes individuals more vulnerable to developing Schizophrenia (SCZ). Many studies have predicted the association between the catechol-O-methyltransferase (COMT) gene Val158Met variant and aggressive attack. We aimed to investigate the association the COMT variant and childhood trauma on aggression in Turkish SCZ patientsThis study included 89 patients diagnosed with SCZ. Childhood Trauma Questionnaire (CTS) and Overt Aggression Scale (OAS) were used to assess childhood trauma and aggression. COMT Val158Met variant was analyzed by PCR-RFLP method from isolated DNAs.There was no statistically significant difference in comparing the COMT genotype distribution and clinical characteristics including suicide attempts, self-destructive behavior, crime history, substance, alcohol and tobacco use. When we evaluate Spearman's rank correlation coefficients between CTQ and OAS, the correlation between the OAS and CTQ scores of the patients was statistically significant except for the sexual abuse subgroup of the CTQ. In the univariate logistic regression analysis, in which the dichotomized OAS score was accepted as the dependent variable, it was found that age, suicide attempt, substance abuse, and CTQ total score significantly predicted the higher OAS scores. In the multivariate logistic regression analysis, which included the variables that predicted OAS significantly, age, suicide attempt, and total CTQ score were determined as independent variables predicting OAS.Because of the phenotypic complexity in SCZ, it is difficult to draw strong conclusions about COMT and to highlight a definitive relationship. Larger-scale studies are needed to examine the multifactorial inheritance pattern of schizophrenia in different dimensions.

Evaluating interleukin-6 levels and the rs1800795 variant in Turkish patients with COVID-19: a prospective cohort study.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is a multisystem disease of global significance. Interleukin (IL)-6 is a soluble cytokine with a pleiotropic effect on inflammation and the immune response. OBJECTIVES: Investigate the relationship between the interleukin 6 (IL6) rs1800795 variant and IL6 level in Turkish patients with COVID-19 disease. DESIGN: Prospective cohort study. SETTING: Tertiary care hospital. PATIENTS AND METHODS: Real-time polymerase chain reaction (RT-PCR)-positive and/or chest computerized tomography (CT) scan-compatible COVID-19 patients were enrolled in the study. The clinical data and whole blood samples were collected from April 1, 2020, to August 1, 2020. IL6 rs1800795 genotyping was performed by the PCR-restriction fragment-length polymorphism (RFLP) method in 148 patients. Serum IL-6 concentrations were measured using the ELISA method in 89 patients. We evaluated the patients in three groups: asymptomatic, symptomatic, and intensive care unit patients. MAIN OUTCOME MEASURES: IL6 rs1800795 genotype frequencies and serum IL-6 levels in COVID-19 patients with different clinical presentations. SAMPLE SIZE: 148 cases. RESULTS: IL6 rs1800795 GG genotype and G allele frequency increased in PCR positive patients compared to PCR-negative patients (p ˂ 0.000). IL6 rs1800795 GC genotype and C allele frequency were lower in PCR-positive patients than in PCR-negative patients. IL6 rs1800795 GG genotype and G allele frequency were higher in asymptomatic patients than in the symptomatic and intensive care unit groups. The IL6 rs1800795 C allele frequency was lower in asymptomatic patients than in the symptomatic and intensive care unit groups. IL6 rs1800795 GG genotype and G allele frequency were higher in CT negative patients than CT positive patients, while IL6 GC genotype and C allele frequency were higher in CT positive patients than negative patients. IL6 level elevation was seen in the asymptomatic patients compared to the symptomatic and intensive care unit groups. CONCLUSIONS: These findings suggest that IL6 rs1800795 may contribute to the susceptibility of COVID-19 in people to Turkish origin. LIMITATIONS: Further large-scale studies in different genetic populations are needed as this is a single-center, prospective study.

Association of MIF-173G/C, IL-4 VNTR, and IL-1RA VNTR variants with FMF-related amyloidosis in a Turkish cohort.

The most important complication of familial Mediterranean fever (FMF) is secondary amyloidosis. The aim of this study is to investigate the risk of developing FMF-related amyloidosis with macrophage migration inhibitory factor (MIF), interleukin 4 (IL-4), and IL-1 receptor antagonist (IL-1RA) variants. This study included 62 FMF patients with amyloidosis, 110 FMF patients without amyloidosis, and 120 controls. The clinical information of the patient groups was compared. MIF-173G/C, IL-4 variant number tandem repeat (VNTR), and IL-1RA VNTR variants were analyzed for all participants. The use of colchicine, pleurisy, and appendectomy was more common in FMF patients with amyloidosis than in FMF patients without amyloidosis. MIF-173G/C C/C genotype and C allele were higher in both patient groups compared to controls. IL-1RA VNTR A1/A2 and A1/A4 genotypes and A1-A4 alleles were more common in both patient groups than controls. The IL-4 VNTR P1 allele was more common in FMF patients with amyloidosis compared to controls. The MIF-173G/C allele and the IL-1RA VNTR A1-A4 allele are associated with FMF in the Turkish population but not with amyloidosis risk in FMF patients. The IL-4 VNTR P1 allele is more common in FMF patients with amyloidosis than in healthy individuals.

Genetic association of the BsmI variant of vitamin D receptor gene with risk of morbid obesity

SUMMARY OBJECTIVE: The aim of this study was to evaluate the vitamin D receptor (VDR) BsmI variant in morbidly obese patients compared with healthy normal controls. METHODS: The study included 103 patients with morbid obesity and 120 healthy individuals serving as normal controls. The DNA samples obtained from blood were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. The gender, age, smoking status, triglycerides, total cholesterol, insulin, mean body mass index, and frequency of allele and genotype of the BsmI variant in the VDR gene in morbidly obese patients were evaluated. RESULTS: The body mass index of the patients was 47.14 ± 7.19. The VDR B/B, B/b, and b/b genotype frequencies were 27.2% versus 28.3%; 54.4% versus 50%; and 18.4% versus 21.7% in the morbidly obese patients and the control group, respectively. There was no statistically significant difference between patients and control subjects in the genotype and allele distribution of the VDR BsmI variant (p>0.05). Both patients and control genotype frequencies are consistent with Hardy-Weinberg equilibrium. CONCLUSION: The BsmI variant in the VDR gene may not seem to predispose to morbid obesity in our study population. Further studies with a larger number of subjects are needed to make a more precise evaluation of this relationship.

Effect of IL-6 -174G/C and -572G/C variants on susceptibility to osteoarthritis in Turkish population.

Osteoarthritis (OA) is a complex disorder characterized by degenerative articular cartilage in which inflammatory mechanisms play a major role in the pathogenesis. Interleukin-6 (IL6), a multifunctional cytokine, can trigger osteoclast differentiation and bone resorption. Our purpose in this study was to evaluate the association of IL-6 -174 G/C (rs1800795) and -572 G/C (rs1800796) variants with the susceptibility to OA. One hundred fifty OA patients and 150 healthy individuals were enrolled in the study. Polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) was used for genotyping the IL-6 gene variants. The results of analyses were evaluated for statistical significance. The pain intensity was assessed using the Visual Analogue Scale (VAS). There was a statistically significant difference in the genotype and allele frequencies of the IL-6 -174 G/C variant between patients with OA and control groups (p = 0.001, p = 0.002, respectively). IL-6 -174 G/C GG genotype and G allele were more prevalent in patients with OA. We found that the IL-6 -572 G/C variant was not different between patients and controls in either genotype distribution and allele frequency. IL-6 174 G/C and -572 G/C loci GG-GG combined genotype was significantly higher in OA patients (p = 0.00). Our study suggests that there was a strong association between the IL-6 -174 G/C variant and OA in the Turkish population. Further studies on populations of different ethnic background are necessary to prove the association of IL-6 variants with OA.

The effect of a 18 bp deletion/insertion variant of VEGF gene on the FMF development.

Objective: Familial Mediterranean fever (FMF) is one of the most common inherited autoinflammatory diseases. Angiogenesis is a feature of inflammatory activation and part of pathogenic processes in autoimmune diseases. Therefore, this study aimed to investigate the role of the Vascular endothelial growth factor (VEGF) gene insertion/deletion (I/D) functional variant in FMF Turkish patients. Methods: MEFV gene mutations were detected in all patients. The FMF patients (N:105) and the healthy controls (N:100) were genotyped for the VEGF I/D variant using PCR followed by agarose gel electrophoresis. The results were statistically analyzed by calculating the odds ratios (OR) and their 95% confidence intervals (95% CI) using the χ2-tests. Results: The mean age of patients was 25.46 ± 10.09. Fifty-nine patients (56.2%) had two or more MEFV gene mutations. The most common MEFV mutation was M694V/M694V. The VEGF I/D variant genotype distribution exhibited a statistically significant difference between the patients and the controls. VEGF I/D genotype was higher in controls compared to patients, while D/D genotype was higher in patients compared to the controls (p = 0.003, p = 0.013, respectively). When we examined the clinical findings, joint pain was more common in patients with VEGF D/D and I/D genotypes compared to I/I genotype (p = 0.043). Although not statistically significant, the most common genotype in patients with two or more MEFV mutations was VEGF D/D (28.6%). Conclusion: The results provided evidence supporting that the D/D genotype of the VEGF I/D variant is associated with an increased risk of FMF in a group of Turkish populations.

Role of VEGF I/D variant in suspectibility to odontogenic cyst formation.

Odontogenic cysts, are located in the jawbones, filled with fluid surrounded by epithelial lining and fibrous connective tissue. Vascular endothelial growth factor (VEGF) can induce physiological and pathological angiogenesis and is an endothelial cell-specific mitogen. The aim of the present study was to investigate whether any possible association between the VEGF insertion/deletion (I/D) variant and odontogenic cyst in Turkish population. Clinical information and venous blood samples were collected from 62 odontogenic cyst patients and 98 healthy controls. DNA was isolated from peripheral blood leukocytes. Genotyping of the VEGF I/D variant was done by the polymerase chain reaction (PCR) method. There was a statistically differece in terms of VEGF I/D allele frequencies between patients and controls. VEGF I/D variant I allele frequency was more prevalant in patients compared to controls (p = 0.006411, OR: 2.08, 95%Cl: 1.322-3.272). A statistically significant association was observed when the patients were compared with the controls according to D/D + I/D versus I/I genotype (p = 0.0508, OR: 1.925, 95%Cl: 0.872-4.246). The genotype distribution of VEGF I/D was not statistically different between patients and controls (p > 0.05). For the first time, our results provided evidence supporting the odontogenic cyst formation associated with the I/D variant at the promoter region of the VEGF gene in a group of Turkish population. Although it was seen in our study that the I/D variant in the promoter region of the VEGF gene supports odontogenic cyst formation, large-scale studies are needed to elucidate the effect of this variant on odontogenic cysts.

Genotype Distribution and Prevalence of High-Risk Human Papillomavirus Infection among Women in Samsun Province of Turkey.

BACKGROUND: The human papillomavirus (HPV) is an important public health problem that can cause cervical cancer. HPVs were classified into high-risk (HR-HPV) and low-risk (LR-HPV) types. In this study, we aimed to determine the prevalence and genotype distribution of HR-HPV infection in Samsun province in Turkey. METHODS: Cervical smear samples taken from 5406 women over a 23-month period were evaluated for the presence of HPV infection. The detection of HPV genotypes was performed using RT-PCR technology. HPV detection and genotyping were performed using RT-PCR method. HR- HPV types are divided into 3 groups as type 16,  type 18 and other types (31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, 68, with or without type 16 and 18).  The results were evaluated statistically. RESULTS: The mean age of HR-HPV positive patients was 39.56 years (20-68 years). The prevalance of HR-HPV types did not differ between different age groups (p˃0.05). Overall, 9.17% of women (496/5406 samples) were found to be positive at least one type of HR-HPV. HPV type 16 was detected in 28.62%, type 18 in 9.67%, and other types in 78.83%. The most common HR-HPV type was other types (p˂0.001). Type 16 was most common than type 18 (p˂0.001). The patients were evaluated by dividing them into 6 age groups. Type 16 positivity was higher in 30-39 ages while type18 and other types positivity were higher in the 40-49 age group. When the 23-month period of HPV test was evaluated according to months and seasons, the highest prevalance was seen in June 2021 and Summer 2021. CONCLUSION: To our knowledge, this is the first large-scale study of HR-HPV prevalence and genotype distribution among women in Samsun Province of Turkey.  The other types containing one or more types made up the majority of the studied population.

VEGF and eNOS variants may influence intervertebral disc degeneration.

BACKGROUND: Intervertebral disc degeneration (IDD) is a common and complex condition. Vascular endothelial growth factor (VEGF) is one of the key regulators of angiogenesis and vascular permeability. Nitric oxide (NO) plays a role in various physiological events. The endothelial nitric oxide synthase (eNOS) that catalyses NO generation are crucial for the regulation of NO level. This study aimed to evaluate the association between VEGF/ eNOS gene variants with IDD. MATERIALS AND METHODS: Two hundred ninety-one subjects (111 IDD patients and 180 controls) were included in the present case-control study. VEGF -2549 insertion/deletion (I/D) and eNOS VNTR variants were analysed by PCR method. The results of this analysis were evaluated for statistical significance. RESULTS: There were no statistically significant differences in genotype and allele distribution of VEGF -2549 I/D/ eNOS VNTR variants between IDD patients and control subjects. We then evaluated the association between the allele frequencies of these variants and clinical features of IDD. Lumber IDD was more common in patients carrying VEGF I/D variant D allele (p < 0.001). Also, patients with lumbar disc herniation, cervical disc herniation, lumbar stenosis, and lumbar IDD had more 4 b allele (p = 0.005, p < 0.001, p < 0.001, and p = 0.03, respectively). CONCLUSIONS: In conclusion, this study demonstrates first time that some clinical characteristics of IDD have been associated with allele frequencies of VEGF -2549 I/D/ eNOS VNTR variants.

What are the roles of global DNA and APC 2 gene promotor hypermethylation in multiple myeloma?

BACKGROUND: In today's practice, gene-based approaches come to the fore in the determination of prognosis and treatment preferences of multiple myeloma (MM). DNA methylation is one of the new approach parameters. DNA methylation occurs by the addition of a methyl group to cytosines in CpG dinucleotides. In this study, besides comparing the global DNA and APC 2 gene promotor hypermethylation between our patients with MM and healthy control group, we aimed to demonstrate the effect of hypermethylation on MM treatment responses and survival. METHODS AND RESULTS: 38 patients diagnosed with MM between January 2016 and January 2020 and 50 healthy controls were included in the study. The initial hypermethylation of the patients and the healthy control group were statistically analyzed. In addition, the increase in hypermethylation in the MM group before and after the first series of treatments were analyzed within themselves. There is a significant difference between the patients with MM diagnosis and the healthy control group in terms of the initial global hypermethylation (P = 0.001). In patients with MM, hypermethylation was significantly higher. Global hypermethylation in the post-treatment measurements was significantly increased in comparison to the pre-treatment state (P = 0.012). In terms of APC 2 promotor gene-specific hypermethylation, no significant differences were detected between pre- and post-treatment values (P = 0.368). CONCLUSIONS: This study represents valuable data with the initial global DNA hypermethylation results in the MM patient group and the increase in hypermethylation post-treatment. it will shed light on future studies.

Medication-related osteonecrosis of the jaw (MRONJ) and eNOS Polymorphisms in multiple myeloma patients: a single center experience.

BACKGROUND: Multiple myeloma (MM) constitutes approximately 10% of hematological malignancies. Bisphosphonates have established themselves in solid organ metastasis and multiple myeloma lytic bone lesions by inhibiting osteoclast activation. Medication-related osteonecrosis of the jaw (MRONJ) emerges as an important complication. Investigating host-based factors, and developing personal risk factors gain importance in the development mechanism of MRONJ. We aimed to reveal the different genotype polymorphisms, and clinical effects of eNOS in patients with a diagnosis of MRONJ in MM patients. METHODS: Medical records and blood samples were collected from 60 MRONJ patients with MM and 60 healthy controls. Inclusion criteria was having an exposed maxillofacial bone for more than eight weeks, a history of bisphosphonates, and no history of radiation therapy for the jaws. eNOS G894T and intron 4 VNTR were calculated by polymerase chain reaction and/or restriction fragment length polymorphism. RESULTS: eNOS G894T and VNTR genotypes and alleles were compared statistically with the healthy control group. There was no significant difference between the two groups. In comparison between G894T and clinical parameters, aphthous stomatitis was more common in TT genotype, while DMFT > 3 was more common in TG-GG genotype (p = 0.035, 0.023). CONCLUSIONS: eNOS induces osteogenesis in bone metabolism, with its regulatory effects on bone remodeling and also NO induced angiogenesis takes place indirectly with its protective effect on endothelial functions. We see that these polymorphisms affecting the entire process of bone remodeling and angiogenesis, especially mucosal damage, which is the triggering factor of MRONJ pathology, have been revealed in the MM patient group. Considering the MRONJ initiating factors, it is necessary to emphasize the importance of our study results. It should be seen as an important step for new studies towards MRONJ and its treatment.

Possible Association of PER2/PER3 Variable Number Tandem Repeat Polymorphism Variants with Susceptibility and Clinical Characteristics in Pancreatic Cancer.

Objective: Pancreatic cancer (PC) is a serious disease with poor outcomes, and its prevalence has been increasing steadily. The circadian rhythm (CR) is involved in multiple physiological events and maintains homeostasis. Alterations in the CR elevate the risk of developing cancer. The present case-control research was carried out to estimate the possible association between PERIOD2/PERIOD3 (PER2/PER3) gene variable number tandem repeat polymorphism (VNTR) variants and PC in the Turkish population. Materials and Methods: A total of 198 subjects (78 patients with PC and 120 healthy controls) were enrolled in this work. Genomic DNA was collected from peripheral blood mononuclear cells, and genotypic analyses was performed using a polymerase chain reaction (PCR) method. Odds ratio (OR) with a 95% confidence interval (95% CI) was calculated using the χ2 test. Results: The frequency of the 4R (4 repeats)/3R (3 repeats), 3R/3R genotypes, and 3R allele of PER2 VNTR in patients with PC was significantly higher than in the control group (p = 0003, p = 0.00004, respectively). PER2 VNTR 4/5 genotype was related to perineural invasion (p = 0.040). The genotype and allele distribution of PER3 VNTR variant did not show any statistical difference between the two groups (p > 0.05). The PER2/PER3 VNTR 4/5-4R/3R combined genotype was increased in the patient group (p = 0.013), while 4/5-4R/4R combined genotype was increased in the control group (p = 0.0001). Conclusions: Our work has indicated that PER2 VNTR 3R allele may play a crucial role in the pathogenesis of PC in Turkish patients, which may become a useful marker for predicting the development of PC. Furthermore, the PER2 VNTR genotype seems to be related to perineural invasion in PC.

TNF-α-308 G/A variant may be associated with bipolar disorder in a Turkish population

ABSTRACT Background: Tumor necrosis factor alpha (TNF-α) is a proinflammatory multifunctional cytokine produced by macrophages. A dysregulation of the immune system contribute to the pathogenesis of bipolar disorder (BD). In this study, we aimed to investigate the relationship between the TNF-α gene -308G/A promoter variant and the risk of BD. Methods: A total of 104 BD patients and 94 healthy controls were enrolled in the study. Genomic DNA was isolated and TNF-α -308G/A variant was analyzed using PCR-RFLP method. Results: TNF-α -308G/A variant GG genotype and G allele were more prevalent in BD patients compared to the controls (p = 0.002 and p = 0.017, respectively). The patients carrying GG genotype had a 5.927-fold higher risk of developing BD. Then, we divided patients into two groups as smokers and non-smokers. TNF-α -308G/A variant GA genotype was higher in non-smoker BD patients than smoker patients (p = 0.027). We found that TNF-α -308G/A AA genotype and A allele increased in smoker patients compared to non-smoker patients (p = 0.008, p = 0.002, respectively). Discussion: Our results provided evidence that TNF-α -308G/A variant may contribute to development of BD in a Turkish cohort. In addition, this variant plays a relevant role in the smoker status of BD.

The miRNA 196a2 rs11614913 variant has prognostic impact on Turkish patients with multiple myeloma.

OBJECTIVE: Multiple myeloma (MM) arises from malignant plasma cells as a single clone in the bone marrow. Accumulating evidences have reported that there is an association between miR-196a2 (rs11614913) variant and various cancers while there were unverified and inconsistent results in MM. The goal of this study is to investigate the impact of the miR-196a2 variant on clinical findings and susceptibility in MM. Two hundred MM patients (156 patients under transplantation of autologous stem cell) and 200 healthy controls included in this study. RESULTS: The statistical analysis showed no significant relationship for allele and frequencies of miR-196a2 genotype between patients and controls (p > 0.05). Log-rank test showed that gender has highly significant impact on both OS and PFS (p = 0.027, p = 0.045). In the univariate analysis, TT genotype (p = 0.022), and CT/TT (p = 0.008) had better OS. In the multivariate analysis, CC/CT-TT were associated with positively OS (p = 0.041). Currently, the most valuable prognostic markers in MM that has clinical implication are genetic abnormalities. It can be concluded from the results that miR-1962a variant is effective in prognosis of the MM. It is believed that these findings will help us understand the molecular basis of disease.

PER3 VNTR variant and susceptibility to smoking status/substance use disorder in a Turkish population

Abstract Background Substance use and smoking exert devastating impact on sleep, especially hindering the ease of falling asleep, compromising the sleep maintenance, and distorting the sleep cycles. PERIOD genes are believed to play a role in individual differences in sleep timing by influencing circadian. Objective The aim of this study was to ascertain whether Per3 VNTR variant affects suspectibility of individuals to substance use disorder (SUD) and smoking status in a Turkish population. Methods A total of 549 subjects, including 212 SUD patients, 160 smoker, and 177 healthy controls, matched by ethnicity, age, and gender, were recruited in a case-control study. Genotyping of Per3 variant was performed using PCR method. Results When the SUD, smoker groups and controls were compared in terms of 5R/5R, 5R/4R, 4R/4R genotypes, no significant difference was observed. Besides, allele frequencies of Per3 VNTR were similar among the groups. Discussion Our data indicate that Per3 VNTR variant is not associated with the risk of SUD and smoking status in our population.

Effect of monoamine oxidase B A644G variant on nicotine dependence and/or schizophrenia risk

Abstract Objectives Schizophrenia (Sch) is a severe and chronic mental illness. Smoking prevalence is higher in patients with Sch than general population. We aimed to investigate the effects of MAOB gene A644G variant on nicotine dependence (ND) and Sch+ND risk in Turkish population and to evaluate by bioinformatic analysis. Methods Present study included 161 individuals with ND, 223 patients with Sch+ND, and 96 non-smoker controls. MAOB A644G variant was analyzed using PCR-RFLP method. As the MAOB gene is located on the X chromosome, each gender was analysed separately. Results The total distributions of AA, AG and GG genotypes of MAOB gene A644G were 44.7%, 22.4% and 32.9% in the ND group, 45.3%, 25.1% and 29.6% in the Sch+ND group and, 44.8, 22.9% and 32.3% in non-smoker controls. No significant differences were observed between groups for the MAOB A644G genotype and allele frequencies when female group compared to male group (p > 0.05). Examination of disease associations of SNPs from each miRNA gene region in GWAS databases yielded results for aging, bipolar disorder, autoimmune, and neurological diseases. Discussion Our results indicate that the MAOB gene A644G variant is not associated with ND and/or Sch susceptibility in the Turkish population.

Effect of a functional variant of tumor necrosis factor-ß gene in temporomandibular disorders: A pilot study.

BACKGROUND: Temporomandibular disorders (TMD) are a group of conditions that cause chronic orofacial pain. The tumor necrosis factor ß (TNF-ß) is a proinflammatory cytokine that is involved in the various aspects of the inflammatory process including organization and maintenance, and in the arrangement of cells at the inflammation site. The purpose of this study was to evaluate the correlation between TNF-ß +252A/G (rs909253) variant and susceptibility to TMD in a Turkish cohort. METHODS: The study included 104 patients (26 males, 78 females) with TMD and 126 healthy controls (44 males, 82 females). The TNF-ß +252A/G variant analysis was based on Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP). RESULTS: There was no deviation from HWA for TNF-ß +252A/G variant in patient and control groups. There was significant difference in genotype and allele frequencies between patient group and control group in terms of TNF-ß +252A/G variant, respectively (P = 0.010, 0.015). A significant increase in the TNF-ß +252 AG genotype and G allele frequencies were observed in TMD patients compared to healthy controls. The individuals with GG genotype and G allele had an increased risk of developing TMD. A statistically significant association was observed when the patients were compared with the controls according to AA genotype vs AG+GG genotypes (P = 0.002, OR: 2.23, 95% CI:1.31-3.82). TNF-ß +252A/G genotype distribution was associated with chewing problems (P = 0.046). CONCLUSIONS: In conclusion, our results provided evidence that TNF-ß +252A/G variant may contribute to TMD development in a Turkish cohort. Further studies are needed to confirm this observation.

Dopamine D4 Receptor Gene Exon III VNTR Variant Influences Smoking Status in Turkish Population.

INTRODUCTION: Dopaminergic gene variants may affect nicotine dependence through their possible impact on the dopamine reward pathway. The purpose of this study is to investigate the relationship between the variable number tandem repeat (VNTR) variant in exon III of the Dopamine D4 receptor (DRD4) gene and genetic predisposition of smoking status in a Turkish population. METHODS: We performed a study comparing 154 subjects as the smoker group, and 111 subjects as the non-smoker group. Genotyping for the DRD4 VNTR variant was performed using a PCR method. RESULTS: There was a significant difference between smoker and non-smoker groups regarding the distribution of the alleles and genotypes of the DRD4 gene (p=0.000, p=0.000, respectively). The 2R allele was higher in the non-smoker group compare to the smoker group (p=0.000). We found that the 2/7 and 4/9 genotypes were more common in smokers than non-smoker group (p=0.037, p=0.028, respectively) while 2/4 genotype was more prevalent in non-smokers than smokers (p=0.000). When the number of repeat alleles (48 bp) are accepted as short (S) if six or less, and as long (L) if seven or more, it was found that the frequency of S/S genotype of the DRD4 VNTR variant was lower in the smoker group and S/L genotype was higher in the smoker group (p=0.006, p=0.006, respectively). The subjects carrying the S/L genotype have a 2.25-fold increased risk for smoking than a non-smoker. CONCLUSION: The results indicated that the subjects carrying DRD4 exon III VNTR S/L genotype have a risk for smoking status in a Turkish population.