Rapid and simple screening of transgenic mice: novel extraction-free, filter-based PCR genotyping from blood samples.

We evaluated the effectiveness of using Flinders Technology Associates (FTA) filter paper for the polymerase chain reaction (PCR) genotyping of transgenic mice. Tail prick blood sample dried on an FTA filter disc was processed for genomic PCR. It is easy and rapid to prepare DNA templates because the protocol is extraction-free and only requires minimal handling of wash briefly bloodstained FTA filter discs. Progeny of a transgene-positive founder mated with wild-type mice was screened for the presence of the transgene by the filter-based PCR using transgene-specific primers. The resulting amplicons with expected sizes of 3134 bp, 1152 bp, 877 bp and 688 bp were robust and reproducible, allowing a distinction between transgenic (n=44) and wild-type (n=47) mice showing no signal. The filter-based PCR screening took only half a day. The present study confirmed the validity and usefulness of the novel rapid extraction-free genotyping method.