Keynote Presentation: Advantages and Disadvantages of Using CRISPR-Cas9 for Model Generation

This session presents two linked talks on CRISPR–Cas9 model generation and sequence validation. Christopher Raymond will discuss how direct zygote editing in mice and rats reduces timelines and costs relative to embryonic stem cell (ES cell) targeting, enables editing across diverse genetic backgrounds and in existing mutant lines, and produces founders within about three months from project start with F1 confirmation in roughly three additional months. He will outline key limitations, including lower efficiency for large homology-directed repair (HDR) knock-ins, risks of random or partial integrations, mosaicism in founders, and complex on-target events.

In the second presentation, Patrick Gordon will focus on complete sequence validation using long-read next-generation sequencing (NGS). He will explain how long reads confirm correct locus targeting while detecting random integrations and concatemers, resolve low-frequency alleles within mosaic founders, sequence across large insertions, and determine whether multiple variants reside on the same allele. He will note that these methods also apply to the characterization of existing mouse models when sequence details or genomic position require clarification.