US Patent 7,534,570. Method for the detection of cytosine methylations in immobilized DNA samples
Inventors: Kurt Berlin, Matthias Ballhause, David Gutig
Describes a method for the analysis of cytosine methylation patterns in genomic DNA samples. In the first step, genomic DNA is isolated from cells or other accompanying materials and bound essentially irreversibly to a surface. Then the DNA is treated, preferably with a bisulfite, in such a way that cytosine is converted into a base that is different in its base pairing behavior in the DNA duplex, while 5-methylcytosine remains unchanged. Reagents are removed in a washing step. Finally, selected segments of the immobilized DNA are amplified in a polymerase reaction and the amplified products are investigated with respect to their sequence.
US Patent 7,534,873. Method and materials for quaternary amine catalyzed bisulfite conversion of cytosine to uracil
Inventors: Gerald Zon, Victoria Boyd
Assignee: Applied Biosystems
Provides methods and materials for the conversion of cytosine to uracil. A nucleic acid, such a gDNA, is reacted with bisulfite, such as magnesium bisulfite, in the presence of a quaternary amine catalyst. Examples of suitable quaternary amine catalysts include, but are not limited to, quaternary ammonium compounds, quaternary alkyl ammonium salts, quaternary alkyl ammonium halides, quaternary methyl ammonium bromide, quaternary ammonium chloride, tetraethylammonium hydroxide, tetraethylammonium chloride, tetrabutylammonium chloride, and tetrabutylammonium bromide. The invention also contemplates kits of premeasured ingredients for carrying out the methods of the invention, either on an individual sample or on several samples.
US Patent 7,527,929. Methods of isolating nucleic acids using multifunctional group-coated solid phase carriers
Inventors: Kevin McKernan, Erik Gustafson, Adrianne Brand
Assignee: Agencourt Bioscience
The invention is directed to a method of isolating a target nucleic acid species from a mixture. In the methods, the mixture is combined with solid phase carriers with a surface comprising multiple functional groups, one of which reversibly and selectively binds the target species. In a particular embodiment, the mixture is combined with solid phase carriers with a first functional group that reversibly binds nucleic acids, and a second functional group that selectively and reversibly binds the target nucleic acid species, thereby producing a first combination. The first combination is maintained under conditions appropriate for binding of the nucleic acids to the first functional group and binding of the target nucleic acid species to the second functional group. The solid phase carriers are separated from the first combination, and combined with an agent that selectively removes either the nucleic acid from the first functional group or the target nucleic acid species from the second functional group of the solid phase carriers, thus isolating a target nucleic acid species from a mixture comprising several nucleic acid species.