DNA of six donors from a multi-generation family was diluted to mimic low-quantity DNA, and the final amounts of DNA were 100 nanograms (ng), 10 ng, 1 ng, 0.5 ng, and 0.1 ng for each sample. In addition, the DNA was also degraded and the fragment sizes were approximately 2500 base pairs (bp), 800 bp, 400 bp, and 150 bp, respectively. These samples were finally detected using the Infinium Asian Screening Array (ASA; Illumina Inc., San Diego CA), with which about 650,000 SNPs were genoyped.