As identical twins get older, their DNA methylation patterns begin to diverge and because of this effect, University of Huddersfield researchers say it's possible to tell DNA samples gathered from identical twins apart.
As they report in Analytical Biochemistry, researchers led by Huddersfield's Graham Williams used bisulfite treatment followed by high-resolution melting curve analysis to differentiate between five sets of monozygotic twins.
"Consequently, if one DNA sequence is more methylated than the other, then the melting temperatures of the two samples will differ — a difference that can be measured, and which will establish the difference between two identical twins," Williams tells the Daily Mail.
He notes, though, that if the twins are young or have always lived in similar environments, the differences in their DNA methylation levels may not be substantial enough to tell them apart.
"Nevertheless, we have demonstrated substantial progress towards a relatively cheap and quick test for differentiating between identical twins in forensic case work," Williams adds.