| CPC C12Q 1/6858 (2013.01) [C12Q 1/6827 (2013.01); C12Q 1/686 (2013.01)] | 21 Claims |
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1. A method for identifying the presence or absence of one or more minor nucleic acid species in a sample, comprising:
(a) obtaining nucleic acids from a sample that includes a target nucleic acid, wherein the target nucleic acid has a major nucleic acid species and one or more minor nucleic acid species wherein each minor nucleic acid species is a lower frequency or copy number variant of the major nucleic acid species and is present at a frequency or copy number that is less than about 10% of the frequency or copy number of the major nucleic acid species, wherein “about” means±10% of the indicated value;
(b) contacting the nucleic acids of (a) with one or more extension primers, each of which comprises an oligonucleotide that hybridizes to the target nucleic acid, under extension conditions comprising a chain terminator specific for the major nucleic acid species and one or more chain terminators specific for the one or more minor nucleic acid species, wherein the concentration of the chain terminator specific for the major nucleic acid species is between 1% to 20%, or 0.5% to less than 20%, or 0.1% to 10%, or 0.01% to 10%, or 0.01% to 5% of the concentration of each of the chain terminator(s) specific for the minor nucleic acid species and wherein, if a ddNTP chain terminator is present in the extension conditions, the same dNTP is absent from the extension conditions, whereby the one or more extension primers are extended by the chain terminators, thereby generating chain terminated extension products corresponding to the minor nucleic acid species and/or chain terminated extension products corresponding to the major nucleic acid species; and
(c) analyzing the extension products of (b), thereby identifying the presence or absence of the one or more minor nucleic acid species.
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