Association of MDR1 (C3435T) polymorphism and resistance to carbamazepine in epileptic patients from turkey

Background and Aims: We investigated the prevalence of this multidrug resistance 1 gene (MDR1) polymorphism in drug-responsive versus drug-resistant epilepsy patients treated with carbamazepine (CBZ), which is a substrate of this protein. Methods: We genotyped the C3435T variant of MDR1 in 97 patients treated with CBZ monotherapy who had been on stable doses for more than 1 month. Our control group included 174 healthy individuals. Plasma CBZ concentrations were also measured using fluorescence polarization immunoassay. Results: We could not demonstrate any statistically significant relationship with the genotypes among drug-resistant patients (n = 44). The frequency of the homozygous mutant (TT) genotype was 15% in drug-responsive patients, 11.3% in drug-resistant patients and 25.8% in the control group. We also did not observe any significant correlation between the presence of a specific allele and CBZ plasma level/dose index. Conclusion: Our study did not support any significant association between the MDR1 (C3435T) polymorphism and resistance to CBZ in epilepsy patients from Turkey. Copyright (C) 2007 S. Karger AG, Basel

Analysis of ACE2 and TMPRSS2 coding variants as a risk factor for SARS-CoV-2 from 946 whole-exome sequencing data in the Turkish population

Heterogeneity in symptoms associated with COVID-19 in infected patients remains unclear. ACE2 and TMPRSS2 gene variants are considered possible risk factors for COVID-19. In this study, a retrospective comparative genome analysis of the ACE2 and TMPRSS2 variants from 946 whole-exome sequencing data was conducted. Allele frequencies of all variants were calculated and filtered to remove variants with allele frequencies lower than 0.003 and to prioritize functional coding variants. The majority of detected variants were intronic, only two ACE2 and three TMPRSS2 nonsynonymous variants were detected in the analyzed cohort. The main ACE2 variants that putatively have a protective or susceptibility effect on SARS-CoV-2 have not yet been determined in the Turkish population. The Turkish genetic makeup likely lacks any ACE2 variant that increases susceptibility to SARS-CoV-2 infection. TMPRSS2 rs75603675 and rs12329760 variants that were previously defined as common variants that have different allele frequencies among populations and may have a role in SARS-CoV-2 attachment to host cells were determined in the population. Overall, these data will contribute to the formation of a national variation database and may also contribute to further studies of ACE2 and TMPRSS2 in the Turkish population and differences in SARS-CoV-2 infection among other populations