What's the Connection between Hpa II and CpG Islands?

 
Epigenetics is all the rage today but the idea that gene expression could be regulated by modifying DNA and/or chromatin has been around for three decades.

Methylation is one of the ways that DNA can be modified and methylation at specific sites can be heritable. This observation grew out of studies on restriction/modification systems where DNA is protected from the action of restriction endonucleases by methylating the bases.

I didn't realize that the study of restriction enzymes led to the discovery of methylated regions of eukaryotic DNA. Find out how by reading an interview with Adrian Bird in PLoS Genetics: On the Track of DNA Methylation: An Interview with Adrian Bird.

This is also a good example of chance and serendipity in science. You can't plan for this stuff to happen—but that doesn't prevent politicians and administrators from trying.

---