How does methylation affect genes?

Produced on site at New Scientist Live 2016! This was a question from the #MendeleyWall, a giant wall in the Mendeley booth where people wrote down the questions they had for science.
Illustrated by Claudia Stocker (vividbiology.com), narrated by Lisa Dennison (sciencesketches.org).

[@michaelduggan8798]

A great introduction to methylation.