Usually when you hear about translational research it involves taking findings from mice and applying them to humans. But Dr. Richard Saffery’s group from the University of Melbourne, apparently inspired by their upside-down geography, decided to celebrate opposite day. They realized that while the mouse is an excellent model for epigenetic research, there is no genome-wide DNA methylation equivalent to the HM450 Bead Array, which is the current gold standard for large-scale human bisulfite analysis. So, they went on to see if the arrays could measure DNA methylation in mouse DNA.
Now I’m sure most of you are wondering what type of madness would inspire such a creative application. So in anticipation your genius questions, we went ahead and contacted the authors.
It turns out that the authors have worked extensively on using these arrays for a childhood leukemia study and all of those crazy mouse researchers (yours truly included) would come up to them and say: “This is a great platform, I want to do it in mouse”. Well, Nick Wong, lead author of the study, finally got sick of “always having to back away and say this is human only”.
The premise of their research was that the array wouldn’t discriminate between highly conserved, and theoretically identical, sequences shared between mice and humans.
They figured that it was those sequences that everyone was most interested in anyways, so they gave it a shot. They estimated the probes in silico using a range of short read aligners and then tested it experimentally to show how it can be done.
Lo and behold they found that:
- 13,715 probes from the HM450 BeadChip uniquely matched the bisulfite converted reference mouse genome (mm9).
- They also found that the same technical robustness of this popular array for human studies holds true for mouse DNA on the probes that were usable. Gotta love evolution!
Wong concludes, “in light of the absence of a dedicated mouse DNA methylation bisulfite array, the HM450 Bead Array is a viable alternative to measuring large numbers of CG loci”.
Find out what human bisulfite arrays can do for your mouse models in Genomics, May 2013