Contamination of corn grain for human consumption with transgenic sequences in Paraguay

María Elena Damús Melgarejo,Juliana Moura Mendes Arrua,Julio Masaru Iehisa,Pastor Enmanuel Pérez Estigarribia,Cinthia Carolina Cazal Martínez,Andrea Alejandra Arrua

doi:10.1590/fst.35718

María Elena Damús Melgarejo, Juliana Moura Mendes Arrua + Show 4 more

Open Access

https://doi.org/10.1590/fst.35718

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Abstract

Abstract Corn is one of the most important economic, social and cultural agricultural products in Paraguay, being the main ingredient of several typical foods. Due to the cross-pollination of this plant, it can be contaminated with transgenic maize pollen found in nearby fields. The general objective of this research was to evaluate the presence of transgenic sequences in corn grains marketed in the Departments of Itapua, Alto Parana and Canindeyu for the preparation of flour for human consumption. We studied 18 samples of corn kernels marketed for the preparation of flour from the Departments of Itapua, Alto Parana and Canindeyu. The DNA was extracted using the Trimethyl Ammonium Bromide (CTAB) protocol. For the detection of the transgenic sequences, the polymerase chain reaction (PCR) method was used. The bands were analyzed visually and using the ImageJ program. The results showed the presence of 5 positive samples for the P-35S-CaMv promoter and 5 samples for the T-nos terminator, none of them presented both sequences sought in the same construction; this indicates that 10 of 18 samples were contaminated with transgenic sequences. These findings show that transgenic products are available in Paraguayan local markets without consumers being aware of this situation.

Highlights

Maize is one of the most important agricultural products worldwide, in terms of quantities produced, consumed and marketed (Wu, 2015)
Because the country has no regulation related to transgenic corn for human consumption, and labeling, the consumers have knowledge of what they are consuming and can make decisions regarding the acquisition of these products. Considering all these aspects, the present work we evaluated the presence of transgenic sequences in corn grains commercialized for human consumption in the Departments of Itapúa, Alto Paraná and Canindeyú
Origin Itapúa Itapúa Itapúa Itapúa Itapúa Itapúa Itapúa Itapúa Alto Paraná Alto Paraná Alto Paraná Alto Paraná Alto Paraná Canindeyú Canindeyú Canindeyú Canindeyú Canindeyú Itapúa Itapúa synthase terminator (T-NOS), present in the construction of 95% of the transgenic corn events (Zahradnik et al, 2014) by using the primers of P-35S-F and P-35S-R that allow to amplify a fragment of 161 bp and T-nos-F and T-nos-R, which amplify a fragment of 130 bp

Summary

Introduction

Maize is one of the most important agricultural products worldwide, in terms of quantities produced, consumed and marketed (Wu, 2015). New hybrids and transgenic varieties with better agronomic characteristics, resistance to different diseases, pests, and abiotic stresses (Alvarez et al, 2006; Nicolia et al, 2014; Cámara Paraguaya de Exportadores y Comercializadores de Cereales y Oleaginosas, 2016). As it is a cross-pollinated plant, there is a possibility that an accidental mixture between the genetically modified (GM) and non-GM material from nearby crops will occur (Devos et al, 2005). For a GM event to be commercialized, it must be approved by the National Commission on Agricultural and Forestry

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