2 kV 24 s injections, respectively. A 1.5 kV 5 s injection on an Applied Biosystems® 3130 Series Genetic Analyzer was used with one donor to reduce signal saturation. Full profiles were detected for extracted DNA and nonFTA punches at all cycle numbers tested. FTA® card punches generated full profiles at both 27 and 28 cycles. At GDC-0199 datasheet the lowest cycle number tested, 26 cycles, 98% of alleles were called; 11 of the 12 FTA® card punches yielded

full profiles, while one yielded only a partial profile. This sample gave exceptionally low signals compared to the other two replicates from the same donor’s FTA® card. With all substrates, peak heights rose steadily with each additional cycle, as expected, and signals were often saturated at the highest cycle number tested. Signal strength with increasing cycle number using solid support materials was highly variable but collectively Rigosertib chemical structure resulted in signal increases similar to extracted DNA. Robust amplification was observed using cycle numbers lower than suggested at multiple sites, demonstrating the recommended cycle numbers can accommodate a range of material sources. When following the recommended template quantity and cycle numbers, artifacts in D18S51 at 214 bases, TH01 at 76 bases, and D12S391 at 176–180 bases commonly remain under the minimum

threshold. Increased sample signal, particularly at high cycle number, directly correlated with an increase in the incidence of called artifacts and artifact peak height. Departures from the optimal annealing

temperature can reduce the yields or generate artifacts which can affect data interpretation. Annealing temperatures 2 °C above and below the recommended annealing temperature of 59 °C were evaluated by amplifying extracted DNA and FTA® card punches. Samples were detected using an Applied Biosystems® 3130 Series Genetic Analyzer with a 3 kV 5 s injection. Full profiles were observed for extracted DNA and FTA® card punches at all temperatures tested: 57 °C, 59 °C, and 61 °C. A slight increase in artifacts was observed at 57 °C, two degrees below the recommended annealing temperature. An off-ladder artifact in D18S51 at 214 bases and an artifact in D12S391 at 180 bases were observed only in extracted DNA samples (Supplemental Fig. 11). These artifacts were below the 50 RFU minimum analytical threshold at 59 °C but, at 57 °C, increased slightly to rise above the threshold. Figure options Download full-size image Download high-quality image (173 K) Download as PowerPoint slide Extensive master mix optimization was performed during development to achieve robust amplification without the introduction of nonspecific artifacts. However, a number of inhibitors and common template storage buffers can affect the available magnesium within a reaction.