Natural hybridization between transgenic and wild soybean genotypes

Abstract

Cultivation of transgenic soybean lines [Glycine max (L.) Merr.] and the international trade of their seeds has led to an increased focus on the potential risk of gene flow from transgenic to wild soybean (Glycine soja Sieb. & Zucc.) in countries such as China, Russia, Korea, and Japan, which are the centers of soybean domestication. The degree of natural hybridization between three wild soybean accessions and three transgenic soybean lines that produce recombinant proteins (EGF, IGF-1, and TRX) for use in the skin care industry was estimated under field conditions over 2 years. The wild soybean accessions were sown earlier than the transgenic soybean lines to synchronize the flowering periods. One single hybrid was detected among 16,343 progenies in 2017 and 12 among 333,243 progenies, in 2018. The rate of gene flow from the three transgenic soybean lines to the three wild soybean accessions ranged between 0% and 0.0519% in the 2 years of study. Further studies are required to determine whether the transfer of transgenes (egf, igf-1, and trx) from transgenic to wild soybean alters the ecological fitness of hybrid progenies and the consequences of transgene flow.