Transgene-product expression levels in genetically engineered breeding stacks are equivalent to those of the single events.

Transgene product expression levels are measured in genetically engineered (GE) crops containing single transformation events and the measured expression levels are then utilized in food, feed, and environmental safety assessments as part of the requirements for de-regulation of the event. Many countries also require measurement of expression levels and safety assessments for GE breeding stacks, even though the breeding stacks are composed of single events that have been previously assessed. Transgene product expression levels were measured in tissues of maize, soybean, and cotton breeding stacks and each of their component single events. Expression levels in the breeding stacks were plotted against expression levels in the single events to quantify the ability of the single events to predict transgene product expression levels in the breeding stacks. These results indicate that transgene product expression levels in single events are a reliable indicator of expression levels in breeding stacks. Based on these results it is concluded that safety assessments for breeding stacks can be conducted using transgene product expression levels from single events.

Agronomic performance of insect-protected and herbicide-tolerant MON 89034 × TC1507 × NK603 × DAS-40278-9 corn is equivalent to that of conventional corn.

Agronomic characteristics of genetically modified (GM) MON 89034 × TC1507 × NK603 × DAS-40278-9 (PowerCore™ Enlist™), MON 89034 × TC1507 × NK603 (PowerCore™), and DAS-40278-9 (Enlist™) corn, a non-GM near-isogenic hybrid, and 2 commercial non-GM hybrids were assessed in a field study to determine if the agronomic performance of the GM corn hybrids is equivalent to that of non-transgenic hybrid corn. The MON 89034 × TC1507 × NK603 × DAS-40278-9 hybrid corn was developed through stacking of 4 individual transgenic events, MON 89034, TC1507, NK603, and DAS-40278-9 by traditional breeding and contains the cry1A.105 and cry2Ab2 (MON 89034), cry1F and pat (TC1507), cp4 epsps (NK603) and aad-1 (DAS-40278-9) transgenes. These transgenes encode the proteins Cry1A.105, Cry2Ab2, and Cry1F, which confer insect resistance, PAT, CP4 EPSPS, and AAD-1, which confer herbicide tolerance. The following agronomic characteristics were assessed in the study: initial and final stand count, seedling vigor, time to silk, time to pollen shed, pollen viability, plant height, ear height, stalk lodging, root lodging, days to maturity, stay green, disease incidence, insect damage, herbicide injury, and yield. The agronomic assessment was conducted in 2 regions of Brazil (Indianopolis-MG; Cravinhos-SP). The agronomic attributes for all GM entries were statistically indistinguishable from the non-GM near-isogenic hybrid. In addition, most of the agronomic assessments fell within the range of the commercial varieties included in the study. Taken together, MON 89034 × TC1507 × NK603 × DAS-40278, MON 89034 × TC1507 × NK603, and DAS-40278-9 were found to be agronomically equivalent to non-GM corn.

Stacking transgenic event DAS-Ø15Ø7-1 alters maize composition less than traditional breeding.

The impact of crossing ('stacking') genetically modified (GM) events on maize-grain biochemical composition was compared with the impact of generating nonGM hybrids. The compositional similarity of seven GM stacks containing event DAS-Ø15Ø7-1, and their matched nonGM near-isogenic hybrids (iso-hybrids) was compared with the compositional similarity of concurrently grown nonGM hybrids and these same iso-hybrids. Scatter plots were used to visualize comparisons among hybrids and a coefficient of identity (per cent of variation explained by line of identity) was calculated to quantify the relationships within analyte profiles. The composition of GM breeding stacks was more similar to the composition of iso-hybrids than was the composition of nonGM hybrids. NonGM breeding more strongly influenced crop composition than did transgenesis or stacking of GM events. These findings call into question the value of uniquely requiring composition studies for GM crops, especially for breeding stacks composed of GM events previously found to be compositionally normal.