השוואת שיטות

	מחקר אסוציאציות אפי-גנום-רחב (EWAS)	ניתוח eQTL
תחום	ביואינפורמטיקה	ביואינפורמטיקה
משפחה	Process / pipeline	Process / pipeline
שנת המקור	2008–2011 (term and framework established c. 2011)	2001 (term coined); widely adopted after 2005
הוגה השיטה	Rakyan, Down, Balding & Beck (conceptual framework); Illumina arrays enabled large-scale application	Ritsert C. Jansen & Jan-Peter Nap
סוג	Population-scale epigenomic association study	Association mapping method
מקור מכונן	Rakyan, V. K., Down, T. A., Balding, D. J., & Beck, S. (2011). Epigenome-wide association studies for common human diseases. Nature Reviews Genetics, 12(8), 529–541.	Jansen, R. C., & Nap, J.-P. (2001). Genetical genomics: the added value from segregation. Trends in Genetics, 17(7), 388–391.
כינויים	EWAS, methylome-wide association study, epigenetic association study, DNA methylation association study	eQTL mapping, expression QTL analysis, transcriptomic QTL analysis, eQTL study
קשורות	5	6
תקציר	An epigenome-wide association study (EWAS) is a hypothesis-free, genome-scale method that systematically tests whether epigenetic marks — predominantly CpG-site DNA methylation — differ between individuals with and without a trait, disease, or exposure. By scanning hundreds of thousands of genomic positions simultaneously, EWAS identifies loci where the epigenome is reproducibly associated with a phenotype, offering a layer of biological regulation that classical GWAS does not capture.	eQTL analysis identifies genomic loci (variants, typically SNPs) whose genotype statistically associates with variation in the expression level of one or more genes. By jointly profiling DNA-level variation and RNA-level expression in the same individuals, eQTL studies decode the regulatory grammar of the genome — revealing which variants control how much a gene is transcribed, in which tissues, and under what conditions.