Methods and compositions are provided for making non-human animals with reduced tolerance of a foreign antigen of interest and making antigen-binding proteins against that foreign antigen of interest using such animals. The methods and compositions employ CRISPR/Cas9 systems using multiple guide RNAs to reduce or eliminate expression of a self-antigen homologous to or sharing an epitope of interest with the foreign antigen of interest or to reduce or eliminate expression of an epitope on the self-antigen that is shared with the foreign antigen of interest.
