Trem2^{em2(TREM2*R47H)Aduci}

The targeting vector is designed to replace mouse genomic DNA between the initiator translation codon in exon 1 and the translation termination codon in exon 5 with the corresponding mutant human genomic DNA sequence flanked by loxP sites. An FRT-flanked neomycin resistance cassette was inserted in the 3' UTR. The human TREM2 sequence contained a CGC to CAC mutation at position 47 resulting in an arginine to histidine mutation (R47H) orthologous to the location of human SNP rs75932628. Human SNP rs75932628 has been found to be one of the strongest genetic risk factors for late-onset Alzheimer's disease (AD). To ensure normal levels of TREM2*R47H transcripts, ssODN repair template, tracrRNA and CAS9 nuclease were introduced into the cytoplasm of Trem2tm1(TREM2*R27H)Aduci-derived zygotes with well recognized pronuclei to remove both loxP sites and the remaining FRT site. This also served to restore the mouse 5'; UTR and 3'; UTR sequences. (J:101977)