User:Ericgarika/Article2improvement

Editing Article
Family-based, adoption, and twin studies have indicated that there is a strong ( 50%) heritable component to vulnerability to substance abuse addiction.

Especially among genetically vulnerable individuals, repeated exposure to a drug of abuse in adolescence or adulthood causes addiction by inducing stable downregulation or upregulation in expression of specific genes and microRNAs through epigenetic alterations. Such downregulation or upregulation has been shown to occur in the brain's reward regions, such as the nucleus accumbens. (See, for example, Epigenetics of cocaine addiction.)

Proposed Edit
I choose to edit the article above because it lacks citations, overall structure, and supporting evidence regarding the mechanism by which up- and downregulation of can exert an effect on addiction. I would begin by explaining what microRNAs are, which have been correlated to drug addiction, and begin to tie the importance of regulation in the brain's reward pathways, especially in the striatum. My proposed edit begins in the second sentence and is as follows:

Especially among genetically vulnerable individuals, repeated exposure to a drug of abuse in adolescence or adulthood causes addiction by inducing stable downregulation or upregulation of specific genes and microRNAs, short non-protein-coding that act like post-translation regulators, to cause epigenetic alterations. (Nestler pg. 632)