Genetic Modified Food, Medical Research on Genetic Engineering

Genetically modified (GM) foods are commonly referred to crop plants created for human or animal consumption using the latest molecular biology techniques. These plants have been modified in the laboratory to enhance desired traits such as increased resistance to herbicides or improved nutritional content. Genetic engineering can create plants with the exact desired trait very rapidly and with great accuracy via gene isolation, thermal tolerance, for example, can be transferred from the host species to the target species. The new GM plant will thus gain drought tolerance as well. Not only can genes be transferred from one plant to another, but genes from non-plant organisms also can be used. The best known example of this is the use of B.t. genes in corn and other crops. B.t. (Bacillus thuringiensis), is a naturally occurring bacterium that produces crystal proteins that are lethal to insect larvae. B.t. crystal protein genes have been transferred into corn, enabling the corn to produce its own pesticides against insects such as the European corn borer.

GM food crops are modified to be pest and disease resistance, herbicide tolerant, or tolerant of extreme weather and temperature. In addition some are modified for specific purposes such as increasing nutritional values in food, for
pharmaceuticals and phytoremediation whereby plants are used to solve soil and groundwater pollution; thus plants like poplar trees have been genetically engineered to clean up heavy metal pollution from contaminated soil.

Pest and disease resistance:

Farmers typically use of chemical pesticides annually. However, consumers do not wish to eat food that has been treated with pesticides because of potential health hazards namely affecting marine and human life. Growing GM foods such as B.t. corn can help eliminate the application of chemical pesticides and reduce the cost of bringing a crop to market. Furthermore, the crops are kept fresh for a longer period of time, increasing its shelf-life.

Herbicide Tolerant:

Weed elimination is a necessary chore in commercial agriculture and the use of herbicides is common practice. In order for the crops not to be contaminated, plants are genetically-engineered to be resistant to a very powerful herbicide thus preventing environmental damage by reducing the amount of herbicides needed. This ensures that farmer can spend less on herbicides and the frequency of its application.

Extreme weather and temperature tolerant:

An antifreeze gene from cold water fish is introduced into plants such as tobacco and potato. These allow plants to tolerate cold temperatures that would normally kill unmodified seedlings. In addition GM plants are also created to withstand long periods of drought or high salt content in soil and groundwater to enable people to grow crops in formerly inhospitable places. This is due to land scarcity and this would alleviate stress for more land.

Increasing nutritional values in food:

Malnutrition is common in third world countries. However, rice does not contain adequate amounts of all necessary nutrients to prevent malnutrition. Rice is genetically modified to contain additional vitamins and minerals, so nutrient deficiencies could be alleviated. For example, researchers at the Swiss Federal Institute of Technology Institute for Plant Sciences have created a strain of "golden" rice containing an unusually high content of beta-carotene (vitamin A). Now plans are underway to develop golden rice that has increased iron content.

Pharmaceuticals:

Medicines and vaccines often are costly to produce and sometimes require special storage conditions not readily available in third world countries. Researchers are working on developing edible vaccines in tomatoes and potatoes. These vaccines will be much easier to ship, store and administer than traditional injectable vaccines.

However GM food have their negative effects such as being an environmental hazard, whereby they cause unintended harm to other organisms, cause undesirable adaptations to current species of organisms and cross-breeding with compatible GM plants which results in new species of plants, risks to humans, for instance the problem of allergenicity and unknown effects on humans, and patenting whereby the companies monopolize the trades of GM food crops.
Last year a laboratory study was published in “Nature” showing that pollen from B.t. corn caused high mortality rates in monarch butterfly caterpillars. Unfortunately, B.t. toxins of the GM corn kill many species of insect larvae indiscriminately as it is not possible to design a B.t. toxin that would only kill crop- damaging pests and remain harmless to all other insects. Mosquitoes have developed resistance to the now-banned pesticide DDT and many people are concerned that insects will become resistant to B.t. or other crops that have been genetically-modified to produce their own pesticides. "Superweeds" which is the result of cross-breeding of a herbicide tolerant GM plant and a compatible natural species of plant are herbicide tolerant as well. Hence new and stronger herbicides need to be manufactured. This also indicates that other introduced genes may cross over into non-modified crops planted next to GM crops.

Research shows that many children in the US and Europe have developed life-threatening allergies to peanuts and other foods due to the possibility that introducing a gene into a plant may create a new allergen or cause an allergic reaction in susceptible individuals. Furthermore, there is a growing concern that introducing foreign genes into food plants may have an unexpected and negative impact on human health. A recent article published in Lancet examined the effects of GM potatoes on the digestive tract in rats. This study claimed that there were appreciable differences in the intestines of rats fed GM potatoes and rats fed unmodified potatoes. Though scientists claim GM has no harm on humans, reality states that many in Less Developed Countries have developed a rare disease, which seems to be on the rise.

In the medical sector, A’ Star has recently been delving into the realm of genetic engineering of stem cells with the aim of discovering new medicinal applications.

They chose to work on the genetic engineering of stem cells have the potential to replace any and all cells in the human body, potentially even those in a severed spinal cord or severely damaged or amputated organs such as kidneys, as well as having the potential to treat terminal illnesses such as cancer or neurological disorders such as Parkinson’s disease.
Current research projects include the general research of stem cells for use in the field of cell therapy which encompasses all the above mentioned applications of stem cells and more, creating models of mammalian development and disease states so as to help with both diagnosis of hard-to-spot diseases as well as the treating of them, and to help map out the neural pathways of a human being.

There is, however, much controversy surrounding stem cells as previously, it was only possible to extract stem cells from embryos. As such, there is religious opposition to the research, as they believe that this is unethical as they are taking the lives of the embryos.

BY: Sakthibalan S/o Balathandautha and Yang Weihao Walter 10S01

Insertion of foreign genes and Cloning

Genetic engineering requires modern and advance technology thus it is going to widely used and dependent in the future when science has been further enhanced. It has already been explore in the last century and in the initial stages of implementation and usage in the twenty first century, mostly in research and development sector and science. There are four different aspects of genetic engineering which is cloning, insertion of foreign genes in an organisms mainly animals, genetically modified food and for research in the medical sector.

Firstly, the insertion of foreign gene(s) into animals’ genome is known as transgenic. These animals created from transgenesis are useful as disease models, animals which are genetically manipulated to display disease symptoms so that effective treatment can be studied.

As a result, transgenic animals are created: transgenic pigs that will serve as a source of transplanted human organs for humans, transgenic cattle, such as the first transgenic cow, Rosie in 1997, to produce milk enriched with particular human proteins to help in some treatments of diseases, and the list goes on. To date, there are three basic methods of producing transgenic animals: DNA microinjection, Retrovirus-mediated gene transfer and embryonic stem cell-mediated gene transfer. However, the success rate of producing transgenic animals individually by these methods is very low and thus, it is probably more efficient to use cloning techniques to increase their numbers.

Transgenic process is preferred to over selective breeding, as the development of traits in animals is made possible in a shorter time and with more precision, resulting in the breeding of large number of offspring of a certain species and the increase in yield for livestock farmers, especially to meet the rising demands of food consumption.

Moreover, the insertion of foreign gene into animals’ genome can also be used in gene therapy, where it can help treat certain diseases or slow down the progression of the disease such as the lung disease, cystic fibrosis. In cystic fibrosis, as the bronchial tubes produce mucus that blocks up the respiratory system, making it difficult to breathe, this disease can be treated by replacing defective genes in damaged airway cells with healthy genes, with the use of vectors.

However, as there are two sides to the coin, inserting foreign gene(s) into animals will also give rise to disadvantages. Nature is an extremely complex inter-related food web consisting of many species, resulting the loss of genetic diversity should the favourable traits inserted be the same. Moreover, insertion of the same favourable genes may lead to the whole species being wiped out if the genes inserted are not resistant to an unknown potent virus, which may be introduced into the environment. Introducing genetically modified genes may have an irreversible effect with consequences yet unknown. Also, the consumption of such animals may pose unknown health and medical risks to the consumers. In gene therapy, if a gene inserted in the body cells find its way into the ova or sperms, and mutates, it may affect the offspring of the patient.

In conclusion, transgenesis shall be our last resort if the alternative measures to meet the demands of the population have been exhausted and were not successful.

Secondly, cloning brings the possibility to clone organs that could be use for organ transplant thus donors are not needed. Moreover, cloning technology enables scientist and researchers to find out more about disease causing genes and how to cure them with the different types of cloning technology like DNA cloning, reproductive cloning and therapeutic cloning. However they do not realize the social implications on the cloned individual as well to the society. In addition to those implications is the difficulty to clone an organism as the scientific knowledge to know what their initial stages of development are and the technology used still requires improvements. The most well known cloned animal is Dolly the sheep, a successful experiment but most do not realise that among the 276 experiments conducted only Dolly came out a success. This indicates that cloning technology is still pretty unreliable and not yet dependable in the present. However the negative impacts are far-reaching with long-term effects. One of the risks are that it interferes with evolution as it removes independent assortment process as well as cross-linking that is carried out to form gametes with different genetic material than their parents. As a result, it could distort generation lines and family relationships, limit genetic differentiation that allows us to adapt to changes in our environment and ensures human life is unique. Ethical issues arise as ‘spare parts’ for their original counterpart instead of as unique individuals and the process of cloning is unnatural, thus they are taken seriously by the public especially by religious body.

Furthermore, reproductive cloning is expensive and highly inefficient evident from the low success rates as well ascomplications with the clone state of health. Cloned animals tend to have more compromised immune function, higher rates of infection, tumour growth and other disorders. Moreover, they have been known to die mysteriously from the extensive research conducted and the sudden death of Dolly as an example. Therefore this technology still requires further development before it is used in large scale and the social issues are not as severe once the public accepts clones into their society.

By: Tan Wan Ting and Nur Afiqah Bte Dzulkifley 10S01