Methylated-Specific PCR - (Jul/04/2005 )

Hello, I'm Maria and I'm a postgraduate student on Molecular Pathology and toxicology. I was hoping If it is possible to help me with something concerning MS-PCR analysis. It is known that when the DNA is treated with bisulphite both its 2 strands are no longer complementary (since the unmethylated sites the Cytosine is converted to thymine). I wanted to know which of the two strands of DNA is amplified from the methylated primers?..
Thank you very much

Usually the top strand or sense strand is amplified for methylation analysis. You can also study the other strand. Methylation is supposed to be symmetric.

totally agreee with pcrman, might I add that mammalian systems have symmetrical methylation. Plants have both symmetrical and assymetrical methylation ie:strand specific methylation.

cheers
Nick

Thank you Nick for the correction.

wasn't really a correction but an addendum

Thank you very much. Obviously then the primers of use should be designed appropriately for the sense strand???...Right?

Amalthea,

you are absolutely correct :-)