The discovery of new and effective treatments for human cardiovascular diseases requires the Identification and validation of novel disease mechanisms. Recently, studies of genomic variation entered a new phase. In which unbiased genome-wide association studies (GWAS) can identify novel genetic loci associated with common diseases. We have recently described 95 loci associate with blood lipid levels-LDL cholesterol (LDL-C), HDL cholesterol (HDL-C), or triglycerides, which are strongly associated with risk for myocardial infarction (Ml) In the NHLBl Framingham Heart Study (FHS) and other population cohorts. Much work will be needed to convert the novel associations into functional insights and, ultimately, therapies to reduce the risk of Ml. A key step is to determine how these genetic loci affect phenotypes in human tissue types relevant to lipid metabolism, principally liver and adipose. We have performed expression quantitative trait locus (eQTL) analyses of genotype vs. gene expression in surgical liver and adipose tissue samples from patients;from this work, we found a strong association between an LDL-C- and Ml-associated SNP on chromosome 1p13-rs12740374-and hepatic expression of the S0RT1 gene. However, these studies were limited by scarcity of tissue and the inability to address key cellular phenotypes such as lipoprotein secretion. Thus, there is a need to establish infinitely renewable sources of hepatocytes and adipocytes from patients of defined genotypes. We have developed the ability to obtain reprogrammed induced pluripotent stem (IPS) cells via peripheral blood cell (PBC) collection. We have also developed a novel technology to accelerate and scale up IPS generation, without any genomic alteration, using in vitro transcribed RNAs encoding reprogramming factors. Finally, we have established protocols to differentiate iPS cells into functional hepatocytes and adipocytes. Our consortium comprises investigators from the FHS, the Harvard Stem Cell Institute (HSCI), Massachusetts General Hospital (MGH), and Harvard Medical School (HMS). We are uniquely positioned to develop a library of IPS cell lines and iPS- derived hepatocytes and adipocytes from several hundred FHS participants, who have genome-wide genotype data as well as many cardiovascular phenotypes. We propose to leverage these resources to: (1) develop efficient protocols to obtain IPS cell lines from blood samples, followed by differentiation into functional hepatocytes and adipocytes;(2) scale up these protocols to enable high-throughput generation of IPS cell lines, hepatocytes, and adipocytes from ~400 Individuals In the Framingham Offspring Cohort;and (3) perform gene expression and metaboiomic profiling from these hepatocytes and adipocytes, enabling Integrative statistical analyses of genotypes with gene expression and metabolite levels, as well as existing phenotype data such as subclinical measures of atherosclerosis.
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