1999
1995
DNA METHYLATION
DNA methylation is a biological process by which methyl groups are added to the DNA molecule . DNA methylation typically acts to repress gene transcription . In 1975 , DNA methylation was proposed as an important mechanism for the control of gene expression in higher organisms . In 1995 , researchers from MIT published evidence to demonstrate that reduced DNA methylation contributes to the formation of tumours .
EPIGENETICS
Gene expression refers to how often or when proteins are created from the instructions within your genes . While genetic changes can alter which protein is made , epigenetic changes affect gene expression by turning genes ' on ' and ' off .' Epigenetics is the study of how your behaviors and environment can cause changes that affect the way your genes work . Unlike genetic changes , epigenetic changes are reversible and do not change your DNA sequence . In 1999 , a group of researchers from the University of Sydney demonstrated that epigenetic markers can be transmitted from one organism to the next ( i . e ., from parent to child ), affecting the traits of offspring without altering the primary structure of DNA .