across families were excluded from subsequent analysis. Pedcheck identified 3104 Mendelian errors resulting in 7714 lost genotypes and the exclusion of one marker. Third, the error-checking algorithm implemented in MERLIN (Abecasis et al., 2002) was used to assess the probability that each genotype was correctly called. A total of 1867 genotypes with probabilities of less than 0.025 of being correct were removed from further analysis. Following these quality control procedures, a total of 1,269,708 genotypes were accepted for analysis with a success rate of 99.6%.
