For someone who is interested in learning about the discovery of epigenetics, which are the foundational defining papers in the area?
I understand that Robin Holliday was the first to discuss the possible role of DNA methylation in the control of Gene expression. In his paper "The inheritance of epigenetic defects" he presents what is one of the first modern formulations of what we now regard as epigenetics. The term "epigenetics" itself was coined by Conrad Waddington although this predated our modern understanding of heredity.
Holliday, R., The inheritance of epigenetic defects, 1987, Science, 238, 4824
There are few single papers that really drive the field by themselves, epigenetics has been a long slow progression (although more recently the definition has been muddied and started to include non-epigenetic modes of gene regulation). A pretty good review of a lot of research, including a more circumspect discussion about what epigenetics is can be found in Youngson and Whitelaw's Annual Review (http://www.ncbi.nlm.nih.gov/pubmed/18767965).
I also found this article in the BBC news: The Ghost in Your Genes
They have shown that a famine at critical times in the lives of the grandparents can affect the life expectancy of the grandchildren. This is the first evidence that an environmental effect can be inherited in humans.
Rodenhiser D, Mann M. 2006. Epigenetics and human disease: translating basic biology into clinical applications. CMAJ : Canadian Medical Association journal = journal de l’Association medicale canadienne 174: 341–8.