Using CRISPR/Cas9 system, P2A-CRE-pA was inserted downstream of exon 10 of the Aldh1a1 gene. The premature termination of the transcript deleted the exons 1113 corresponding to the 100 amino acids (401-500) of the C-terminal, which is essential for enzyme function and stability of Aldh1a1. It is a null allele. The absence of protein products was established by western blot analysis. (J:316743)