Online Mendelian Inheritance in Animals (OMIA): a record of advances in animal genetics, freely available on the Internet for 25 years.

For the last 25 years, Online Mendelian Inheritance in Animals (OMIA) has been providing free global access to an ever-increasing record of discoveries made by animal geneticists around the world. To mark this 25-year milestone, this document provides a brief account (including some pre-history) of how OMIA came to be; some timelines of important discoveries and advances in the genetics of the animal species covered by OMIA, gleaned from the OMIA database; and an analysis of the current state of knowledge regarding likely causal variants of single-locus traits in OMIA species, also gleaned from the OMIA database.