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Background/Objectives: Genome-wide association studies (GWAS) have identified many loci associated with body mass index (BMI) in many different populations. Variants in the FTO locus are reported to be one of the strongest genetic predictors of obesity. Recent publications pointed also to a topologically associated domain (TAD) which is identified as a novel region affecting BMI. The TAD area encompasses the IRXB cluster (IRX3, IRX5, IRX6), FTO and RPGRIP1L genes. Subjects/Methods: In this study, we investigated the relationship between variation of the FTO and IRX genes and obesity in Poles. We presented a case—control association analysis (normal versus overweight and/or obesity group) of Polish adult individuals (N = 5418). We determined whether or not the chromosomal region 16:53 500 000–55 500 000 contains polymorphic variants which are correlated with BMI in Polish population, including sex and age stratified analysis. Results: The obtained results showed that the problem of weight-height abnormalities differently affects populations of Polish women and men (χ2 = 187.1; p<0.0001). From 353 SNPs enrolled to this study, 86 were statistically significant (highest χ2 = 15.72; p = 7.35E-05 observed for rs1558902). Linkage disequilibrium (LD) analysis revealed 61 blocks in the tested region of chromosome 16, with 24 SNPs located within the same block (block 8) of approximately 40 kb, in almost complete LD (|D’|>0.98, r2>0.80). We confirmed presence of the genetic susceptibility loci located in intron 1 of the FTO gene, which were correlated with BMI in our study group. For the first time, our analyses revealed strong association of FTO intronic variants (block 8) with overweight in group of men only. We have also identified association of the IRX region with overweight and/or obesity in Polish individuals. Conclusion: Our study demonstrated how tested SNPs make differential contributions to obesity and overweight risk. We revealed sex dependent differences in the distribution of tested loci which are associated with BMI in the population of Poles. [ABSTRACT FROM AUTHOR]

Objective: Endometriosis is a common gynaecological disease, associated with severe pelvic pain and reduced fertility; however, molecular mechanisms remain largely unknown. Genome-wide association studies (GWAS) are able to identify genetic loci, which can play significant role during endometriosis development.Aim: The study aimed at localisation of new genes and chromosomal loci, the nucleotide variants of which determine the level of susceptibility to endometriosis.Study Design: Blood samples from 171 patients with endometriosis were used as material for studies. The patients were recruited to the study at the Department of Operative Gynaecology of the Institute of the Polish Mother's Memorial Hospital in Lodz. A control group (n=2934) came from the POPULOUS collection registered at Biobank Lab, Department of Molecular Biophysics, University of Lodz. DNA of the patients with endometriosis was compared with DNA of women free from that disease, the comparison being supported by GWAS.Results: Genome-wide significant correlation was identified between one new, not previously described, single nucleotide polymorphism (SNP), rs10129516, localised on chromosome 14 in intergenic region between PARP1P2 and RHOJ genes (p=1.44×10-10, OR=3.104, 95% CI=2.329-4.136) and endometriosis. We have also identified significant association with endometriosis of 18 SNPs localised on chromosome 6 in position range 31883957 - 32681631 (C2 and HLA-DRA genes region) with the lowest observed p value for rs644045 in C2 gene (p=2.04×10-8, OR=1.955, 95% CI=1.541-2.480).Conclusion: Reported GWAS identified the novel loci associated with endometriosis in Polish women, not previously reported. The most interesting observation shown in our study are regions associated with susceptibility to endometriosis of loci located near C2, HLA-DRA and RHOJ genes.Results: of that study did not correspond to previously published data about polymorphism in that regions and further evaluations are necessary in groups with higher numbers of patients to explain whether the above-mentioned genetic variant may be the risk factor for pathogenesis of endometriosis. [ABSTRACT FROM AUTHOR]