dbSNP genotyping resources Since its initiation, dbSNP at NCBI with support from the biomedical community has accumulated over 5.3 million unique clustered / mapped genetic variations (reference SNPs) in Humans, and just over a half a million Mouse SNPs. A SNP genotype is a list of an individual’s (or strain’s) alleles at a single SNP. The growth of deposited SNP genotypes in dbSNP has proceeded at an exponential rate with 16.1 million Human genotypes and over 400 thousand Mouse genotypes currently available through the dbSNP web site. The pace of SNP genotype submissions is also expected to accelerate even further with long-waited HAPMAP project data. In this talk I will discuss the current status of dbSNP genotype data and resources, as well as several challenges that we face to make this data accessible and useful to the public.