Patent ID: 8409804

Claim:
A method of amplifying a plurality of GC-rich DNA molecules without cloning, comprising: providing a plurality of DNA molecules, said plurality having molecules comprising one or more regions that are GC-poor and having molecules comprising one or more regions that are GC-rich; subjecting the plurality of DNA molecules to denaturation and renaturation conditions to substantially denature GC-poor regions but not to denature GC-rich regions, wherein the GC-rich regions are referred to as thermo-resistant DNA molecules; attaching an adaptor by ligation to ends of the thermo-resistant DNA molecules to produce adaptor-linked thermo-resistant DNA molecules; and performing one of the following without cloning: (a) subjecting the adaptor-linked thermo-resistant DNA molecules to one or more methylation-sensitive restriction enzymes, thereby cleaving non-methylated DNA and retaining methylated DNA fragments to produce methylated GC-rich DNA fragments; and PCR amplifying the methylated GC-rich DNA fragments; or (b) subjecting the adaptor-linked thermo-resistant DNA molecules to one or more methylation-specific restriction enzymes, thereby cleaving methylated DNA and retaining non-methylated DNA fragments to produce non-methylated GC-rich DNA fragments; and PCR amplifying the non-methylated GC-rich DNA fragments.