Project description:A genetic study of the PRF1 gene has shown association of several polymorphisms with multiple sclerosis (MS). Haplotype analysis identified risk haplotypes strongly associated with male patients having the primary-progressive form of MS (PPMS). Gene expression microarrays were performed in 10 male PPMS patients carrying the risk (n=6) and protective haplotypes (n=4) in order to identify pathways associated with the risk haplotypes. Pathway analysis revealed overrepresentation of the cell killing gene ontology category among down-regulated genes in patients carrying risk haplotypes compared with patients carrying protective haplotypes.
Project description:Mitochondrial DNA (mtDNA) haplotypes are associated with phenotypes and disease. To understand how mtDNA haplotypes induce these characteristics, we used four embryonic stem cell lines that have the same set of chromosomes but possess different mtDNA haplotypes. We show that mtDNA haplotypes influence changes in chromosomal gene expression and affinity for nuclear-encoded mtDNA replication factors to modulate mtDNA copy number, two events that act synchronously during differentiation. Global DNA methylation analysis showed that each haplotype induces distinct DNA methylation patterns, which, when modulated by DNA demethylation agents resulted in skewed gene expression patterns that highlight the effectiveness of the new DNA methylation patterns established by each haplotype. The haplotypes differentially regulate α-ketoglutarate, a metabolite from the TCA cycle that modulates the TET family of proteins, which catalyse the transition from 5-methylcytosine (DNA methylation) to 5-hydroxymethylcytosine (DNA demethylation). Our outcomes show a direct link between mtDNA haplotypes and DNA methylation profiles.
Project description:A genetic study of the PRF1 gene has shown association of several polymorphisms with multiple sclerosis (MS). Haplotype analysis identified risk haplotypes strongly associated with male patients having the primary-progressive form of MS (PPMS). Gene expression microarrays were performed in 10 male PPMS patients carrying the risk (n=6) and protective haplotypes (n=4) in order to identify pathways associated with the risk haplotypes. Pathway analysis revealed overrepresentation of the cell killing gene ontology category among down-regulated genes in patients carrying risk haplotypes compared with patients carrying protective haplotypes. Number of samples analyzed: 10 Protective haplotype samples: UOM982, EMA1473, MMC-998, CDP1842 Risk haplotype samples: UUS1554, RAU1550, RPS1011, AGS1013, PFB1530, MGA1014