Your Query returns 6 Accession Numbers:

Query TermAccessionNCBI TaxonidSynonymsPhenotype (OMIM) *
Nkx2-9BC0410909606NKX2.8    NKX2H    NKX2-8   
Nkx2-9NM_0143609606NKX2H    NKX2.8    NKX2-8   
Nkx2-9NM_00870110090Nkx2.9    tinman    Nkx-2.9   
Nkx2-9NT_03955110090
Nkx2-9Y1574110090
Nkx2-9AF20204010090

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

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Text2Knowledge ... Yong Huang 2002