The Ac/Ds transposon system in maize causes insertion mutations in closely linked locations. It has been applied to target specific chromosomal regions in several plant species [35, 36]. In soybean, the feasibility of Ac/Ds was tested by sequencing flanking regions of 200 individual mutants and was validated by isolating a gene involved in male-fertility . Similarly, mPing, a miniature inverted repeat transposable element (MITE) from rice was evaluated in soybean . mPing was shown to transpose to unlinked regions with a strong preference for gene-containing regions . Tnt1, a tobacco retrotransposon, was effectively transformed into soybean and was shown to be re-activated by tissue culture .