Your Query returns 6 Accession Numbers:

Query TermAccessionNCBI TaxonidSynonymsPhenotype (OMIM) *
ESRNM_1529597955ER[a]    NR3A1    zfER[a]    esr1   
ESRNM_00795610090ERa    Estr    ER[a]    Estra    Nr3a1    ERalpha    Esr1    133430
ESRNM_0001259606ER    Era    ESRA    NR3A1    ESR1    133430
EsrNM_01268910116ER-alpha    RNESTROR    Esr1   
ESRM126749606133430
ESRM120759606133430

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

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