Aflatoxin-free transgenic maize using host-induced gene silencing

Aflatoxins are toxic metabolites produced by some species of Aspergillus fungi that can occur on numerous crop plants. When ingested by animals, aflatoxins cause health problems including liver cancer and stunted growth. Thakare et al. used host-induced gene silencing (HIGS) to block aflatoxin production in maize. They introduced into maize a kernel-specific RNAi construct specific for a gene aflc encoding a key enzyme in alfatoxin biosynthesis. When the resulting plants were inoculated with Aspergillus, no aflatoxin was detectable and no other differences between the engineered and control plants were observable. The authors emphasize that the success of this effort was due to their efforts to identify regions of the aflc gene with no sequence homology to the maize genome. Science 10.1126/sciadv.1602382