MSAB lecture : The FALSE promises of genetic engineering
In conjunction with Malaysian Society of Applied Biology (MSAB) Annual General Meeting on 16th August 2011, a public lecture on "The promises of genetic engineering in food and agriculture" was scheduled in the morning. The speaker is Dr. Micheal Hansen from USA Consumer Union. To our surprise, the actual title presented on that day is "The FALSE promises of genetic engineering in food and agriculture". Genetic engineering promises high yield, less pesticide, less herbicide, more healthy and safe food with the goal to feed to the world. Dr. Micheal Hansen explained why most of them are myths.
Myth 1 : US safety assessment is very high
Truth: There is no safety assessment conducted by FDA except for Favour Savior tomato. Some companies volunteer and submit summary to FDA but no specific details on how the assessment was done.
Myth 2: GM crops increase yield
Truth: The yield of Bt soybean is generally no better than the wild type variety. The yield drag makes sense because the energy to produce food will be channeled to produce resistance. Also, the yield depends on the variety used for transformation. Most high yield plant varieties are difficult to be transformed, and therefore, the varieties used in GM crops have lower yield. Generally, the yield is lower compared to conventional varieties as improved varieties (in terms of yield, disease and environmental resistance) are constantly released into the market. Therefore, a farmer planting conventional varieties produces higher yield each year than one that is planting GM crops. It's not possible for GM crops have to be commercialized at the same speed as conventional varieties.
Myth 3: GM crops reduce pesticides
Truth: Pesticide usage DO decrease in GE crops for the first few years BUT increase and exceed the conventional cultivar usage. Based on 9 year data, pesticide is used more on secondary pests. Surveys in china showed that Bt farmers reduce 46% pesticide on biolworm but spend 40% more on secondary pesticide.
Myth 4: GM crops reduce herbicides
Truth: Use of RR crops caused weeps to have roundup resistant. In some places, manual weep removal has to be applied because herbicides don’t work anymore. This is labour intensive and thus, increase the production cost.
Myth 5: GM crops do not cause allergy or immunology stimulation
Truth: GE crops do give some serious consequences in allergic and immunology reactions because the protein produced are not naturally found in the organisms. Some thinks this will increase our immunity which is a good thing but others don’t. A research looked for allegens using 6 amino acid search and found several proteins. Cry1A is a potent simulator of immune system and can survive digestion although there are claims that it will be digested in 30 seconds. There is a survey that showed Bt cotton cause allergic reactions in farmers and factory workers.
Golden Rice can save a million kids a year... think again!
In 2000, the headline "This rice can save a million kids a year" appeared in Time front cover. Golden rice is a variety of Oryza sativa produced through genetic engineering to synthesize beta-carotene (a precursor of pro-vitamin A) aimed to reduce blindness and malnutrition worldwide. The problem is an average person needs to eat 10kg a day to get enough daily intake of vitamin A. Then, comes GR2 in 2004 claimed to have 23 times more carotenoid than GR1. In this improved variety, two genes are transformed in rice which are responsible for converting lycopene to Beta carotene. Beta carotene can either be converted to Vitamin A or oxidized to form toxic which caused birth effects. There are doubts that vitamin A might be degraded during harvesting, storage and cooking. Since vitamin A is not a water soluble vitamin, GR has to be consumed with oil to allow its absorption. The other problem is GR is only available in Oryza sativa japonica (the temperate rice). Oryza sativa indica is widely planted in Asia such as Thailand and China. Importing golden rice will increase the price and reduce the number of people who can afford this staple food. I think this criticism is valid.
However, if you visit the GoldenRice website, you will find a FAQ here explaining: 1) GR is not expected to solve deficiency of vitamin A; 2) there is no danger of vitamin A toxicity 3) Natural lipid in rice will help absorption of vitamin A. Do note that most scientific references are 1995-2002.
So who's right and who's wrong?
This talk has got me start thinking about GE from a consumer aspect because I have been taught and repeatedly told about the advantages of GE. I remember Malaysia was being criticized by a representative from Sygenta for not planting GM crops during BioMalaysia Conference 3 years ago. The issues with GE are no longer about public acceptance of GMO and horizontal gene transfer. As a scientist, I think the real question is how to solve all these problems? The solutions are proteomic to understand allergic reactions, transformation efficiency and gene expression studies to increase yield ... resulting in more tax money put into research.
P.S. Another interesting thing is 43 genes are up/down regulated in GM plant compared to wild type. Such a huge effect on gene expression due to the insertion of one gene!
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