The EpiTwin project examines twins that are discordant, where one twin is affected with a specific condition and the co-twin is unaffected.
The EpiTwin Project began in July 2010 and was a grant that ran for 5 years, funded as a Senior Investigator Award to Professor Spector by the European Research Council.
The main objective of the project was to look at identical twins that were discordant (where one twin is affected and the co-twin is unaffected) for specific traits associated with a number of common complex disease of aging (http://www.epitwin.eu/).
Epigenetics is a naturally occurring phenomena that act like a light switch to turn genes on and off as we grow in utero and develop from a child to an adult. (http://www.sciencedaily.com/releases/2014/04/140428074640.htm). However, it is possible that environmental factors such as smoking (http://www.medicaldaily.com/how-smoking-changes-your-genes-cigarettes-linked-epigenetic-alterations-265265) cause epigenetic changes that lead to the onset of a number of diseases due to our genes being turned on or off when they are not meant to be.
There are a number of different ways in which epigenetic changes alter the way that DNA functions without changing the actual code (http://circ.ahajournals.org/content/123/19/2145.full), but the EpiTwin project concentrated on the methylome and the way in which genes are switched off by the addition of a methyl group to the CpG islands on genes (https://www.youtube.com/watch?v=sakHU15cziM).
Using a combination of Methylated Immunoprecitipation Sequencing (MeDIP-seq), 450K Methylation HumanBeadChIP and Targeted Bisulphite sequencing (TEBs), the EpiTwin project found that there were a number of methylation changes present in genes of twins that are affected by diseases such as Depression (http://www.genomebiology.com/content/15/4/R56), Type 2 Diabetes (http://www.nature.com/ncomms/2014/141212/ncomms6719/full/ncomms6719.html) and Breast Cancer (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3534196/) When compared to their twin who was not affected.
The discovery of epigenetic changes such as these can lead us to a greater understanding of what makes us ill or alternatively what keeps us well. It gives us the opportunity to find novel disease biomarkers that can be used to regularly monitor our health to show when a lifestyle intervention such as dietary change may help to reduce the risk of the onset of a common complex disease or alternatively provide a new therapeutic targets that can be used in the treatment of these diseases (http://www.theguardian.com/books/2012/aug/08/identically-different-genes-spector-review).