Why brain neurons in Parkinson's disease stop benefiting from levodopa
 

Modulating global DNA methylation -- either by injecting methionine to increase methylation or applying RG-108, an inhibitor of methylation, to the striatum -- modified the dyskinetic behavior of LID, down or up, respectively.

Still a long way to go
 

The article from ScienceDaily says:

"The treatments we have used here, methionine supplementation or RG-108, are not practical for human use; but they point to the opportunity to develop methylation-based epigenetic therapeutics in Parkinson's disease."

The message I get from the article is that a new research direction has been established in the battle with LID, but it will be quite a few years before PwPs can expect a new drug to become available (if ever).