Online Mendelian Inheritance in Man (OMIM) is a database that keeps track of all known human genes.
It list those which cause genetic disorders, and those which simply cause traits. There are about 8,000 entries for genes, and 15,000 entries for phenotypes, which are (roughly) the feature(s) caused by a person's genes.[1]
When possible it links diseases to specific genes. It provides a useful tool for further research.[2] OMIM is one of the databases housed in the U.S. National Center for Biotechnology Information (NCBI). People search it using the NCBI search menus.[3]