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ADVERSE IMPACTS OF TRANSGENIC CROPS/FOODS :A COMPILATION OF SCIENTIFIC REFERENCES WITH ABSTRACTSvarieties, heighten the importance of establishing baselines of expected isoflavonelevels in transgenic and conventional soy products to ensure uniformity of clinicalresults. Disclosure of the origins and isoflavone composition of soyfood productswould be a valuable adjunct to clinical decision-making.http://online.liebertpub.com/doi/abs/10.1089/jmf.1998.1.2413. Shewmaker CK, Sheehy JA, Daley M, Colburn S and Ke DY (1999) : Seedspecificover-expression of phytoene synthase: increase in carotenoidsand other metabolic effects. Plant J, 20 (4) : 401-412X.A bacterial phytoene synthase (crtB) gene was overexpressed in a seed-specificmanner and the protein product targeted to the plastid in Brassica napus (canola).The resultant embryos from these transgenic plants were visibly orange and themature seed contained up to a 50-fold increase in carotenoids. The predominantcarotenoids accumulating in the seeds of the transgenic plants were alpha andbeta-carotene. Other precursors such as phytoene were also detected. Lutein,the predominant carotenoid in control seeds, was not substantially increased inthe transgenics. The total amount of carotenoids in these seeds is now equivalentto or greater than those seen in the mesocarp of oil palm. Other metabolites inthe isoprenoid pathway were examined in these seeds. Sterol levels remainedessentially the same, while tocopherol levels decreased significantly as comparedto non-transgenic controls. Chlorophyll levels were also reduced in developingtransgenic seed. Additionally, the fatty acyl composition was altered with thetransgenic seeds having a relatively higher percentage of the 18 : 1 (oleic acid)component and a decreased percentage of the 18 : 2 (linoleic acid) and 18 : 3(linolenic acid) components. This dramatic increase in flux through the carotenoidpathway and the other metabolic effects are discussed.http://www.ncbi.nlm.nih.gov/pubmed/10607293(92)