High-throughput knock-in coupling gene targeting with the HPRT minigene and Cre-mediated recombination

Single nucleotide polymorphisms (SNPs) may influence protein function possibly contributing to phenotype; yet, for most SNPs their potential influence is unknown. Here, we present a technique in mouse embryonic stem cells that enables high-throughput knockin (the placement of coding sequences adjacent to a specific endogenous promoter). Our methodology utilizes gene targeting with a combination of two selection cassettes (SAβgeo and the HPRT minigene) along with site-specific recombinases (Cre/loxP and FLP/FRT) to efficiently introduce multiple DNA sequences, including enhanced green fluorescent protein (eGFP), adjacent to the DNA topoisomerase 3β (Top3β) promoter. This technology enables rapid and efficient introduction of DNA sequences to a specific location and advances high-throughput analysis of many SNPs with control for expression and genetic background.