Quality and completeness of SNP databases

To address the quality and completeness of single-nucleotide polymorphism (SNP) databases, we resequenced 173 kb (spanning 17 loci) in 150 chromosomes of west African and European ancestry. Over 88% of SNPs in the public (TSC and BAC overlap) and Celera databases were confirmed in independent resequencing. Approximately 45% of all human heterozygosity is attributable to SNPs already available from the two databases, and of SNPs with minor-allele frequencies >10%, more than half are represented.