Genome-wide association studies (GWAS) have successfully analyzed the genetic basis for disease susceptibility or quantitative trait differences in human populations. Similar to a human association study, GWAS can also be performed in mice by correlating trait values measured in a set (usually ≤ 10) of inbred strains with alleles genotyped at single nucleotide polymorphisms (SNPs), which were selected to represent the genetic pattern within regions of the mouse genome. However, multiple modeling studies and analyses have purported to demonstrate that murine GWAS cannot identify the genetic factors affecting most biomedical traits of interest, due to low power and a high false positive rate [1–3]. The laboratory mouse has been the premier model organism used in biomedical research. It has many unique features that enable biomedical discovery, including: the availability of multiple well-characterized strains, mammalian physiology, a homozygous genome, experiments can be performed under conditions that control environmental variables, and its genome can be genetically modified, which enables the assessment of the impact that allelic variation has on phenotype. It would be very discouraging for all types of genetic research, if we truly could not perform genetic association studies using this model organism.
