Long range PCR was performed to amplify a region spanning 2,523 base pairs of the 5’-end of the transposon in two steps using two nested primers from Tgm9 and two from the mutant MER3 gene of mer3 (S1 Table). The PCR products were amplified using Phusion high fidelity DNA polymerase (Thermo Fisher, USA). Bands of correct size were extracted from a 0.8% agarose gel using IBI gel extraction kit (IBI Scientific, USA). The samples were sequenced using the inner Tgm9 and inner MER3 primers at the DNA Facility at Iowa State University. The resulting sequence was aligned with the Tgm9 (GQ344503.1) and Tgmt* (EU190440.1) sequences.