Your Query returns 3 Accession Numbers:

Query TermAccessionNCBI TaxonidSynonymsPhenotype (OMIM) *
Ext1lNM_018788100902900009G18Rik    Extl3   
Ext1lXM_13084310090Extl1    Extl3   
Ext1lBC065073100902900009G18Rik    Extl3   

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

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Text2Knowledge ... Yong Huang 2002