A method for detecting a first allelic variant of a target sequence in a nucleic acid sample suspected of comprising at least a second allelic variant of the target sequence, comprising: a) forming a first reaction mixture by combining: i) the nucleic acid sample; ii) a first allele-specific primer, wherein an allele-specific nucleotide portion of the first allele-specific primer is complementary to the first allelic variant of the target sequence; iii) a first allele-specific blocker probe that is complementary to a region of the target sequence comprising the second allelic variant, wherein said region encompasses a position corresponding to the binding position of the allele-specific nucleotide portion of the first allele-specific primer, and wherein the first allele-specific blocker probe comprises a minor groove binder; iv) a first locus-specific primer that is complementary to a region of the target sequence that is 3' from the first allelic variant and on the opposite strand; and v) a first detector probe; b) carrying out an amplification reaction on the first reaction mixture using the first locus-specific primer and the first allele-specific primer to form a first amplicon; wherein said carrying out an amplification reaction comprises a 2-stage cycling protocol, comprising a first stage of amplification that employs an initial number of cycles at a lower annealing/extension temperature, followed by a second stage of amplification that employs a number of cycles at a higher annealing/extension temperature, and c) detecting the first amplicon by detecting a change in a detectable property of the first detector probe, thereby detecting the first allelic variant of the target gene in the nucleic acid sample a) forming a first reaction mixture by combining: i) the nucleic acid sample; ii) a first allele-specific primer, wherein an allele-specific nucleotide portion of the first allele-specific primer is complementary to the first allelic variant of the target sequence; iii) a first allele-specific blocker probe that is complementary to a region of the target sequence comprising the second allelic variant, wherein said region encompasses a position corresponding to the binding position of the allele-specific nucleotide portion of the first allele-specific primer, and wherein the first allele-specific blocker probe comprises a minor groove binder; iv) a first locus-specific primer that is complementary to a region of the target sequence that is 3' from the first allelic variant and on the opposite strand; and v) a first detector probe; i) the nucleic acid sample; ii) a first allele-specific primer, wherein an allele-specific nucleotide portion of the first allele-specific primer is complementary to the first allelic variant of the target sequence; iii) a first allele-specific blocker probe that is complementary to a region of the target sequence comprising the second allelic variant, wherein said region encompasses a position corresponding to the binding position of the allele-specific nucleotide portion of the first allele-specific primer, and wherein the first allele-specific blocker probe comprises a minor groove binder; iv) a first locus-specific primer that is complementary to a region of the target sequence that is 3' from the first allelic variant and on the opposite strand; and v) a first detector probe; b) carrying out an amplification reaction on the first reaction mixture using the first locus-specific primer and the first allele-specific primer to form a first amplicon; wherein said carrying out an amplification reaction comprises a 2-stage cycling protocol, comprising a first stage of amplification that employs an initial number of cycles at a lower annealing/extension temperature, followed by a second stage of amplification that employs a number of cycles at a higher annealing/extension temperature, and c) detecting the first amplicon by detecting a change in a detectable property of the first detector probe, thereby detecting the first allelic variant of the target gene in the nucleic acid sample