CxxC domain for isolation and determination of methylation status of CpG islands
A protein domain (CxxC) has been discovered, which is capable of specifically binding non-methylated CpG islands (CGIs). A method for generation of CpG island library and a simple two-step, column-based process have been developed using this protein domain to separate CGIs from bulk DNA.
Diagnostic and prognostic tool
Comparative analysis of methylation status in disease and non-diseased tissues
The use of CxxC domain is validated and published
Patent on CxxC domain, CGI library, and CxxC domain based reagents has been granted in USA, UK, and EU
Available for licensing
The current method employed to analyse CGI methylation are cumbersome, time-consuming, use toxic reagents, and can damage template DNA. Given the importance of CGI methylation in influencing the expression of genes, a new method is required for faster analysis free of DNA damaging chemicals.
Using the CxxC domain, which specifically binds non-methylated CGIs, in a column format, it is possible to generate a complete library of non-methylated CGIs from tissues or cells of interest. Complete isolation of all CGIs is facilitated through the combined use of CxxC and MBD domains, the latter binding specifically to methylated CGIs. Isolation of CGIs using CxxC domain followed by downstream array- or PCR-based analysis allows fast and accurate identification of non-methylated CGIs from the sample of interest.
This method has successfully been applied to various human tissues, available as an array of non-methylated CGIs. The CxxC domain column provides a >50-fold enrichment of non-methylated CGIs from bulk DNA, validating the use of this domain.
- No need of toxic chemicals that damage DNA samples
- Reduced assay time and costs
- Simple, efficient, and reproducible two-step process
Illingworth RS, Gruenewald-Schneider U, Webb S, Kerr ARW, James KD, Turner DJ, et al. (2010) Orphan CpG Islands Identify Numerous Conserved Promoters in the Mammalian Genome. PLoS Genet 6(9): 1001134.
Please note, header image is purely illustrative.