Expression quantitative trait loci

Notes from "A beginner's guide to eQTL mapping"

• Genomic regions that contain DNA sequence variants that influence the expression level of one or more genes
• They are identified by studying a population of genetically different individuals
• The individuals in the population are genetically different but most of the genetic variations do not have any consequence on gene expression
• Two types of data are collected from each individual to identify the sites that influence gene expression
• Each individual is genotyped and their gene expression profile is assayed
• Expression quantitative trait loci (eQTLs) are identified by comparing the genotypes with expression levels using association or linkage analysis
• A statistical test is performed to test whether a sequence variant has an effect on gene expression; individuals are grouped according to their genotype and if the gene expression is significantly higher in one group than the other, there is evidence that the variant (or another in LD) influences the expression of the gene

Reading

• From expression QTLs to personalized transcriptomics - https://www.ncbi.nlm.nih.gov/pubmed/21386863
• The role of regulatory variation in complex traits and disease - https://www.ncbi.nlm.nih.gov/pubmed/25707927
• Transcriptome and genome sequencing uncovers functional variation in humans - https://www.ncbi.nlm.nih.gov/pubmed/24037378
• Understanding mechanisms underlying human gene expression variation with RNA sequencing - https://www.ncbi.nlm.nih.gov/pubmed/20220758