Your Query returns 7 Accession Numbers:

Query TermAccessionNCBI TaxonidSynonymsPhenotype (OMIM) *
Rgp1NM_01264110116Reg    RGPI    LITHOST    RATRGPI    Reg1   
RGP1U315653888
RGP1Z481794932
rgp1X592764530
rgp1AJ2920783635
RGP1AJ01107839947
RGP1NC_0011364932

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

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Text2Knowledge ... Yong Huang 2002