Journal: Upsala Journal of Medical Sciences
Article Title: From early methods for DNA diagnostics to genomes and epigenomes at high resolution during four decades – a personal perspective
doi: 10.48101/ujms.v129.11134
Figure Lengend Snippet: Principle of allele-specific primer extension and genotyping results by allele-specific primer extension: (a) A pair of allele-specific primers with different 3’-ends that are complementary to each mutant or variable SNP allele is immobilized on a microscope slide as small circular arrays (125–150 uM in diameter). The DNA templates are amplified by multiplex PCR. During PC, T7 RNA polymerase promoter is inserted into the 5’-end of the DNA fragments. For genotyping, the PCR products are added to the primer arrays together with ribonucleotides (rNTPs) and a T7 RNA polymerase to generate multiple RNA targets by reverse transcription of each PCR product. Simultaneously with reverse transcription, fluorescent CY5-labeled dNTPs are incorporated into the target molecules in allele-specific primer extension reactions. The fluorescent signals on the microscope slides are quantified using a confocal fluorescence scanner, and the data are interpreted with a custom-designed software. (b) Carrier frequencies of 31 mutations of the ‘Finnish disease heritage’ determined in 2,100 population samples from four geographical regions of Finland.
Article Snippet: We used a microarray format on microscope slides for SNP genotyping with fluorescence detection using four dideoxy nucleotides (ddNTPs) labeled with Tamra (tetramethyl-6-carboxyrhodamine) in four separate reaction mixtures (NEN Life Science Products).
Techniques: Mutagenesis, Microscopy, Amplification, Multiplex Assay, Reverse Transcription, Labeling, Fluorescence, Software