title: A 90-day toxicity study of GmTMT transgenic maize in Sprague-Dawley rats.
abstract: GmTMT transgenic maize is a genetically modified maize plant that overexpresses the γ-tocopherol methyltransferase (γ-TMT) from Glycine max (Gm). The γ-TMT gene was introduced into maize line Zhen58 to encode the GmTMT2a protein which can convert γ-tocopherol into α-tocopherol. Overexpression of GmTMT2a significantly increased the α-tocopherol content in transgenic maize. The present study was designed to investigate any potential effects of GmTMT maize grain in a 90-day subchronic rodent feeding study. Maize grains from GmTMT or Zhen58 were incorporated into rodent diets at low (12.5%), medium (25%) or high (50%) concentrations and administered to Sprague-Dawley rats (n = 10/sex/group) for 90 days. The negative control group of rats (n = 10/sex/group) were fed with common maize diets. Results from body weights, feed consumption, clinical chemistry, hematology, absolute and relative organ weights indicated no treatment-related side effects of GmTMT maize grain on rats in comparison with rats consuming diets containing Zhen58 maize grain. In addition, no treatment-related changes were found in necropsy and histopathology examinations. Altogether, our data indicates that GmTMT transgenic maize is as safe and nutritious as its conventional non-transgenic maize.
authors.affiliation: Key Laboratory of Food Safety Risk Assessment of Ministry of Health, National Center for Food Safety Risk Assessment, Beijing 100021, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Fang
authors.affiliation: Key Laboratory of Food Safety Risk Assessment of Ministry of Health, National Center for Food Safety Risk Assessment, Beijing 100021, China.
authors.forename: Yongquan
authors.initials: Y
authors.lastname: Feng
authors.affiliation: Key Laboratory of Food Safety Risk Assessment of Ministry of Health, National Center for Food Safety Risk Assessment, Beijing 100021, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zhi
authors.affiliation: Biotechnology Research Institute, National Key Facility of Crop Gene Resources and Genetic Improvement, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors.forename: Lan
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Food Safety Risk Assessment of Ministry of Health, National Center for Food Safety Risk Assessment, Beijing 100021, China. Electronic address: yuzhou310@163.com.
authors.forename: Zhou
authors.initials: Z
authors.lastname: Yu
authors.affiliation: Key Laboratory of Food Safety Risk Assessment of Ministry of Health, National Center for Food Safety Risk Assessment, Beijing 100021, China. Electronic address: jiaxudong@cfsa.net.cn.
authors.forename: Xudong
authors.initials: X
authors.lastname: Jia
mesh_terms: D000818:Animals; D005260:Female; D008297:Male; D008780:Methyltransferases / Q000235:genetics*; D010940:Plant Proteins / Q000235:genetics*; D030821:Plants, Genetically Modified / Q000633:toxicity*; D017207:Rats, Sprague-Dawley; D013025:Glycine max / Q000201:enzymology*; D059550:Toxicity Tests, Subchronic; D003313:Zea mays / Q000235:genetics*
chemical_list: D010940:Plant Proteins; D008780:Methyltransferases; C047259:gamma-tocopherol methyltransferase
keywords: Feeding study; Rats; Toxicity; Transgenic maize