GM Free Cymru

CRUCIAL PAPER 9: Transgenic plant DNA found in animal tissues (pigs)

Citation: Mazza R, Soave M, Morlacchini M, Piva G, Marocco A.(2005)
Assessing the transfer of genetically modified DNA from feed to animal tissues.
Transgenic Res. 2005 Oct;14(5):775-84.

NB. This paper relates not to animal harm arising out of the feeding of GM materials, but to the transfer of transgenic DNA from GM plants into animal tissues -- something that the GM industry (and the regulators) have long claimed to be impossible.

Fragments of the cry1A(b) genes in the blood, liver, spleen, kidney and muscle of pigs fed with GM maize.

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 diet-derived 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 CrylA(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.


"For EFSA to reaffirm its statement that transgenic DNA had not been found in animal tissue when the two studies by Mazza et al. (2005) and Sharma et al. (2006) clearly showed they had, is seriously misleading and ignores the scientific facts. It is unclear why EFSA refuses to state that transgenic fragments have been detected in tissues of farm animals. It is also unclear why the European Commission continues to ask EFSA for scientific advice when the advice it has provided in this case was not scientific but selective and biased."

See Werner Mueller (2008) "EFSA misleads the European Commission and the public over GMOs"