Your Query returns 2 Accession Numbers:

Query TermAccessionNCBI TaxonidSynonymsPhenotype (OMIM) *
zgc:56642BC0490567955MGC56642    RPS21   
zgc:56642NM_2011917955RPS21    MGC56642   

Search Again
* OMIM link based on symbol match for human and mouse.

Google

Text2Knowledge ... Yong Huang 2002