Horizontal transfer of antibiotic resistance genes into microflora and blood cells in rats fed on GM-diet

Abstract

Abstract Background With regard to the extensive production of genetically modified organisms, scientists focused on the safety of antibiotic resistance marker (ARM) genes present in GM-crops produced for the consumption of human or animal. We investigated the possible transfer of these genes to the microflora present in the gastrointestinal tract and blood cells of two groups of Male Wistar Albino rats fed on a transgenic diet containing the ARM genes nptII and aadA for 90 days. The conventional PCR was employed to screen for the presence of nptII and aadA genes in the experimental diets, and animals’ samples. Results The occurrence of DNA transfer of nptII and aadA genes from GM-diet to blood and bacterial cells has been unambiguously demonstrated. Results were further confirmed by sequencing and blast analysis, indicating that both transferred segments shared significant alignment with number of Binary and Cloning Vectors with variable similarities. The frequency of transfer of DNA segments from the GM-diet into blood DNA was unexpectedly higher than its transfer to bacterial DNA which may be attributed to a number of factors. Conclusions Our results unambiguously demonstrated the occurrence of DNA transfer of ARM genes (nptII and aadA) from GM plant diet to blood cells and enteric microflora in rats. Results may draw attentions to the importance of exploring the possible effects of transfer of ARM genes horizontally from GM products to consumers and to extend our attentions to the importance of a better understanding of the factors influencing HGT in the intestine of the GM-food consumers.

Keywords

• GMO
• Horizontal gene transfer
• Antibiotic resistance marker gens
• nptII
• aadA gene
• Enteric microflora