This study reports results from genotyping 25 previously implicated SNPs and 207 ancestrally informative markers. All samples and Affymetrix Kit Control DNA (Affymetrix, Santa Clara, CA, USA) were thawed to room temperature. Each sample's concentration was measured using a Nanodrop ND-1000 spectrophotometer (Thermo Fisher Scientific, Pittsburgh, PA, USA), and an aliquot diluted immediately with ddH2O to 150 µg/ml (18.4 µl) into a single well of a barcoded 96-well plate. Samples were processed in this manner sequentially, until all 535 samples were diluted and distributed. Samples were arranged as 23 samples per plate. Twenty-four plates were used to accommodate 535 samples and 24 internal Affymetrix control DNA samples (one per plate), with an additional 17 wells available for 15 randomly selected duplicate samples included to measure concordance rates. All plates were prepared in one afternoon, sealed, and then frozen at −20°C until processed.
