m6dA increases expression of BDNF during fear extinction

This is a big deal actually - the research shows that DNA is also controlled by methylation of adenosine (in addition to well known cytosine methylation).

And this has something to do with fear extinction. Why it’s relevant to ASD - fear extinction plays part in OCD it seems.

The researchers examined the DNA from the fear extinction neurons in those mice, and discovered the presence of a modified adenosine, N6-methyl-2-deoxyadenosine (m6dA), at more than 2800 locations across the genome.

In particular, the team discovered that m6dA accumulates at the gene for brain-derived neurotrophic factor (BDNF), which is known to nurture learning and memory.

Interestingly, m6dA increases expression of BDNF during fear extinction."