Assessing the Transfer of Genetically Modified DNA from Feed to Animal Tissues

Abstract

In Europe, public and scientific concerns about the environmental and food safety of GM (Genetically Modified) crops overshadow the potential benefits offered by crop biotechnology to improve food quality. One of the concerns regarding the use of GM food in human and animal nutrition is the effect that newly introduced sequences may have on the organism. In this paper, we assess the potential transfer of dietderived DNA to animal tissues after consumption of GM plants. Blood, spleen, liver, kidney and muscle tissues from piglets fed for 35 days with diets containing either GM (MON810) or a conventional maize were investigated for the presence of plant DNA. Only fragments of specific maize genes (Zein, Sh-2) could be detected with different frequencies in all the examined tissues except muscle. A small fragment of the Cry1A(b) transgene was detected in blood, liver, spleen and kidney of the animals raised with the transgenic feed. The intact Cry1A(b) gene or its minimal functional unit were never detected. Statistical analysis of the results showed no difference in recovery of positives for the presence of plant DNA between animals raised with the transgenic feed and animals raised with the conventional feed, indicating that DNA transfer may occur independently from the source and the type of the gene. From the data obtained, we consider it unlikely that the occurrence of genetic transfer associated with GM plants is higher than that from conventional plants.

Fate of transgenic DNA and evaluation of metabolic effects in goats fed genetically modified soybean and in their offsprings

“…Although few have found recombinant DNA sequences in any organ or tissue sample from animals fed GM plants (EFSA, 2007), our results showed that small DNA fragments can also be detected in kids organs when mothers are fed GM soybean. Recombinant plant DNA has also been found by other authors as a rare event (Chowdhury et al, 2003a;Mazza et al, 2005;Sharma et al, 2006) in organs and tissues of animals fed GM feeds. On the contrary, studies aiming at verifying the presence of transgenic fragments in milk gave negative results.…”

“…Indeed, the implications of DNA transfer from food containing GM plants to an organism is no higher as compared with DNA transfer from food containing the corresponding conventional plant (Mazza et al, 2005).…”

“…On this basis, a number of GM products have been approved for human consumption, but concerns over safety persist in the public, mainly regarding either the detection of transgenic plant genes and proteins in animal systems or allergenicity and toxicity of GM plants. Furthermore, some authors have shown the possible survival of recombinant plant DNA fragments after digestion, although health implications as well as biological relevance of data are still far from being confirmed (Nemeth et al, 2004;Mazza et al, 2005;Sharma et al, 2006). The absorption of plant DNA across the intestinal barrier is a natural event, as demonstrated by the detection of endogenous plant genes in several animal tissues and products (Reuter and Aulrich, 2003;Tony et al, 2003;Tudisco et al, 2006b).…”

RETRACTED: <i>Gamma-Glutamyl Transferase Activity in Kids Born from Goats Fed Genetically Modified Soybean</i>

“…Transgenic plant DNA has been found by other authors [15][16][17][18][19] in organs and tissues from animals fed GM feeds. On the contrary, in trials carried out on dairy cows fed GM soybean [20], the chloroplast DNA fragments were detected in milk but no transgenic fragments were found.…”

Rotulagem de alimentos que contém Organismos Geneticamente Modificados: políticas internacionais e Legislação no Brasil

“…A complexidade das discussões é decorrente de dois fatores principais: por um lado, a base de conhecimentos científicos sobre as implicações e os impactos da liberação em lar ga escala de plantas transgênicas para o cultivo comercial é ainda insuficiente; por outro lado, a questão das plantas transgênicas enseja uma abordagem inter e multidisciplinar, uma vez que os impactos são diferenciados, os conflitos de interesses são múltiplos e o diálogo apenas re centemente vem se tornando público 4,5 .…”