The mouse phenotypic information described here was obtained from the Mouse Genome Informatics (MGI) database [4] http://www.informatics.jax.org/ Phenotypes, Alleles and Disease Models section. The file used for mouse phenotypic information (see methods) is comprised of 5011 unique genes and 5142 unique phenotypic terms derived from information from specific gene mutations in multiple mouse strains. The mouse phenotypic information had been annotated to the mouse gene mutation records using Mammalian Phenotype terms and codes in the mouse phenotype database as a component of the Mouse Phenotyping Project [5, 13] .