Project description:The objective is to quantify the contribution of genetic and common environmental effects in the familial resemblances of whole blood genome-wide gene expression levels. We also make comparisons with familial resemblances in blood leukocytes genome-wide DNA methylation levels in the same cohort in order to further investigate biological mechanims.
Project description:The primary objective of this prospective observational study is to characterize the gut and oral microbiome as well as the whole blood transcriptome in gastrointestinal cancer patients and correlate these findings with cancer type, treatment efficacy and toxicity. Participants will be recruited from existing clinical sites only, no additional clinical sites are needed.
Project description:BackgroundConsidering the implication of gene expression in the susceptibility of chronic diseases and the familial clustering of chronic diseases, the study of familial resemblances in gene expression levels is then highly relevant. Few studies have considered the contribution of both genetic and common environmental effects to familial resemblances in whole blood gene expression levels. The objective is to quantify the contribution of genetic and common environmental effects in the familial resemblances of whole blood genome-wide gene expression levels. We also make comparisons with familial resemblances in blood leukocytes genome-wide DNA methylation levels in the same cohort in order to further investigate biological mechanisms.ResultsMaximal heritability, genetic heritability, and common environmental effect were computed for all probes (20.6%, 15.6%, and 5.0% respectively) and for probes showing a significant familial effect (78.1%, 60.1%, and 18.0% respectively). Pairwise phenotypic correlations between gene expression and DNA methylation levels adjusted for blood cell heterogeneity were computed for probes showing significant familial effect. A total of 78 probe pairs among the 7,618,401 possible pairs passed Bonferroni correction (corrected P-value = 6.56 × 10- 9). Significant genetic correlations between gene expression and DNA methylation levels were found for 25 probe pairs (absolute genetic correlation of 0.97).ConclusionsFamilial resemblances in gene expression levels were mainly attributable to genetic factors, but common environmental effect also played a role especially in probes showing a significant familial effect. Probes and CpG sites with familial effect seem to be under a strong shared genetic control.
Project description:Atherosclerosis is characterized by thickening of the arterial wall and is the primary cause of the coronary artery disease and cerebrovascular disease, two of the most common causes of illness and death worldwide. One of the leading risk factors for development of atherosclerosis is familial hypercholesterolemia. Familial hypercholesterolemia is an autosomal dominant disorder, which is caused by mutations mainly located in the low-density lipoprotein receptor (LDLR) gene. It is characterized by elevated levels of low-density lipoprotein cholesterol, the presence of tendon xanthomas, and premature cardiovascular disease. Aim of this study was to find atherosclerotic markers in white blood cells of patients compared to healthy controls. None of these patients exhibited symptoms of atherosclerosis by standard diagnostic methods; however, transcriptome analysis of blood RNA indicated changes in ubiquitin proteolysis and cell adhesion system as expected in initiation steps of atherosclerosis. Experiment Overall Design: Five patients diagnosed with Familial hypercholesterolemia and five age, sex, BMI and smoking status matched controls contributed blood from which total RNA from white blood cells was isolated. RNA samples were analyzed using Affymetrix microarrays and two groups were compared for differentially expressed genes.
Project description:Atherosclerosis is characterized by thickening of the arterial wall and is the primary cause of the coronary artery disease and cerebrovascular disease, two of the most common causes of illness and death worldwide. One of the leading risk factors for development of atherosclerosis is familial hypercholesterolemia. Familial hypercholesterolemia is an autosomal dominant disorder, which is caused by mutations mainly located in the low-density lipoprotein receptor (LDLR) gene. It is characterized by elevated levels of low-density lipoprotein cholesterol, the presence of tendon xanthomas, and premature cardiovascular disease. Aim of this study was to find atherosclerotic markers in white blood cells of patients compared to healthy controls. None of these patients exhibited symptoms of atherosclerosis by standard diagnostic methods; however, transcriptome analysis of blood RNA indicated changes in ubiquitin proteolysis and cell adhesion system as expected in initiation steps of atherosclerosis.