Your Query returns 2 Accession Numbers:

Query TermAccessionNCBI TaxonidSynonymsPhenotype (OMIM) *
RSp0311NC_003296267608RS05459    oprM   
RSp0311AL646078305RS05459    oprM   

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

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Text2Knowledge ... Yong Huang 2002