Our A2 genotype detector uses the yeast enzyme flap endonuclease (flappase) to detect a single nucleotide difference between the A1 and A2 alleles of the beta casein protein. For more details on how the system works, see our Project pages. We designed and constructed a flappase basic part (BBa_K3389002) and composite part (BBa_K3389003) for the purposes of expressing a His-tagged flappase enzyme. In addition, our detector system needs both positive and negative control DNA. We produced basic parts for the A1 and A2 Exon 7 portion of the beta casein gene (parts BBa_K3389001 and BBa_K3389000, respectively). Due to the laboratory access constraints imposed by the Covid-19 pandemic, we were only able to characterize the A2 Exon 7 basic part.