Your Query returns 14 Accession Numbers:

Query TermAccessionNCBI TaxonidSynonymsPhenotype (OMIM) *
Cdc21NM_00856510090Mcmd4    mcdc21    Mcm4   
CDC21BC0310619606CDC54    MGC33310    P1-CDC21    hCdc21    MCM4   
CDC21NM_0059149606CDC54    hCdc21    MGC33310    P1-CDC21    MCM4   
CDC21NM_1827469606CDC54    hCdc21    MGC33310    P1-CDC21    MCM4   
cdc21AJ24828729292
cdc21AL1099574896mcm4    SPCC16A11.17    SPCC24B10.01   
cdc21AL1579914896SPCC24B10.01   
CDC21Z749824932
cdc21X588244896
cdc21NC_0034214896SPCC16A11.17   
cdc21NC_000917224325
cdc21U291788355
cdc21NC_00086829292
CDC210N/ATMP1    CRT9   

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

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Text2Knowledge ... Yong Huang 2002