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High-throughput transcriptomic and proteomic data like microarray data are deposited in public databases such as Gene Expression Omnibus (GEO). Omics data integration and processing from different and independent studies is achieved by using efficient and effective computational tools through meta-analysis. Meta-analysis is a statistical powerful tool combining data from numerous studies, minimizes bias and increases statistical power by increasing sample size compared to individual studies. Therefore, we performed a meta-analysis of gene expression data in adipose tissue to identify genes that are differentially expressed between obese and non-obese subjects as well as to detect gene expression signatures, pathways and networks associated with obesity. We identified 821 differentially expressed genes (DEGs) in adipose tissue of obese subjects compared to non-obese. A protein-protein interactions (PPIs) network was reconstructed consisting of 168 proteins. Functional enrichment analysis in the network revealed proteins involved in RNA and energy metabolism. The KEGG pathway analysis revealed 15 enriched pathway terms. Furthermore, multiple testing correction methods identified five statistically significant obesity associated genes (NDUFA12, SFI1, SSB, FAR2 and LACE1) that require further investigation., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Nowadays, obesity is the greatest scourge worldwide, particularly for the developed countries and is a huge burden for the public health. Over the past decade, GWAS have revealed a number of genes associated with obesity. The fat mass and obesity associated (FTO) gene was the first one associated with obesity in a significant number of populations and recent meta-analysis studies confirm this association. FTO is a N-methyladenosine demethylase and in addition to the genetic association, its biological role in the regulation of body weight has been documented. Due to lack of replication regarding FTO association with obesity in the Greek adult population, we analyzed three SNPs, i.e. rs9939609, rs9930506 and rs3751812 in a cohort of 203 adults, comprising of 95 obese, 58 overweight and 50 control individuals. Analysis has shown a significant association for FTO (rs9930506; A/G) 'G' allele with obesity and a difference by 3.2 BMI units between the two homozygotes (AA versus GG). This association, which was detected for the first time in this population, suggests that FTO rs9930506 is a predisposition marker to obesity in the Greek adults, but the results should be taken cautiously due to the limitation of the relatively small sample size of the subjects., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The prevalence of obesity has increased dramatically during the last thirty years in western countries with severe complications for health and economy. Obesity is the outcome of the strong interplay between genetic and environmental factors and is therefore widely expected that the discovery of the many genetic factors underlying the heritable risk of obesity will contribute critically to our basic knowledge of the disease etiopathogenesis and the identification of new targets for therapeutic intervention. The aim of the present study was to assess the genetic contribution of known polymorphisms in two genes that are linked to the pathogenetic mechanism of obesity. Analysis of vitamin D receptor (VDR) TaqI (rs731236; T/C) and fat mass and obesity-associated (FTO) (rs9939609; A/T) [corrected] polymorphisms in 82 obesity subjects and 102 controls showed significant association for VDR TaqI 'T' allele and obesity (OR: 2.07; 1.123-3.816; P=0.019), contributing to an elevated BMI of 3kg/m(2) per risk allele. No association was observed for the FTO polymorphism. These results further support a role for VDR as risk factor for obesity and suggest its further validation in larger independent populations as well as highlight a target for functional analysis towards therapeutic intervention in obese individuals., (Copyright © 2012 Elsevier B.V. All rights reserved.)

We sequenced and analyzed the mitochondrial tRNA(Thr) and tRNA(Pro) genes from brown hare (Lepus europaeus) individuals of different geographic distribution and we investigated the role of various nucleotide substitutions that were detected. We compared these tRNAs with the respective available mitochondrial tRNA genes sequences within Lepus species and among mammals. The mutations that were detected represent specific and conserved polymorphisms that do not seem to affect the structural and functional features that are required for participation of tRNA molecules in mitochondrial protein synthesis. These changes however, possibly reflect on the evolutionary background of the species, which is based on the high intra-genomic variability and the evolutionary dynamic of the mitochondrial DNA. In an attempt to compare the phylogeny that is based on these specific tRNA genes with the phylogeny that is produced from sequencing data of the mitochondrial variable loop, we came up with results that indicate similar phylogeographic clusters. This observation implies that the tRNA mutations that were used for the present study have been well tolerated during evolution and they define an additional genetic and biochemical tag that can be used for such studies. Based on this notion and according to our results, we propose that mitochondrial tRNA genes can be used as valuable auxiliary molecular markers for contemporaneous and linked biochemical and genetic analyses.