BIOSAFETY ISSUES WITH TRANSGENIC CROPS Biosafety means the

BIOSAFETY & ISSUES WITH TRANSGENIC CROPS ‘Biosafety’ means the need to protect human & animal health and environment from the possible adverse effects of the products of MODERN BIOTECHNOLOGY GMOs are emerging as very important tools to solve several current problems; however bio-safety is an equally important concern. Several reports have been published on the negative impact of GMOs on human health risks and environmental and social concerns for the release of GMOs.

Bio-safety of human and animal health 1. Safety issues of source organism and genes • Safety of antibiotic resistance marker [selectable markers – neomycin phosphotransferase (npt II) and Hygromycin (hpt) - reduce the effectiveness of antibiotic to fight disease when these antibiotics are taken with the meal • Use of promoters of virus origin Ex. 35 S promoter of Ca. MV 2. Safety issue of newly developed product (toxicity and allergenicity) • Addition of new genetic material may activate toxic pathways • Changes in nutritional level • Non immunogenic protein could become immunogenic / allergineic

Environmental Concerns Effect of transgenic plants on population of target and non target organism • Insect/microbes population rapidly adapt to environmental pressure • Evolution of new insect biotypes/microbial strain Ex. Superbugs - A superbug is usually defined as a microorganism that’s resistant to commonly used antibiotics • Negative impact on non target organism Development of resistance to herbicide • Gene flow due to cross pollination for the traits involving resistance can result in development of tolerant/resistant weeds that are difficult to eradicate. - Contaminate local variety with transgene Ex. Superweeds - uncontrollable herbicide-resistant weeds Ryegrass highly resistant to glyphosate already found in Austrailia

Impact on biodiversity Sustainable agriculture depends on mixed cropping and crop rotation. Transgenic crop causes reduction in genetic diversity by development and global spread of improved varieties Accidental cross breeding between GMO plants and traditional varieties through pollen transfer can contaminate the traditional local varieties with GMO genes resulting in the loss of traditional varieties of the farmers. GM crops could lead to erosion of biodiversity and 'pollute' gene pools of endangered plant species. Genetic erosion has occurred as the farmers have replaced the use of traditional varieties with monocultures.

Socio-economic and ethical Issues • Unacceptable intervention in “God’s creation violating barriers in natural world” • Objections to consuming animal genes in plants and vice-versa • Demand for GM and Non GM food labeling • Biopiracy, or foreign exploitation of natural resources • Critics claim that patent laws give developers of the GM crops a dangerous degree of control over the food supply • Domination of world food production by a few companies

Cisgenic and intragenic • The public hesitance in European and other countries to accept transgenic products and their risk to health and environment is also linked to the introduction of transgene into crop species of genetic material derived from alien organisms. • To overcome the notorious aversion against transgenic, two new genetic engineering approaches, namely ‘cisgenesis or cisgenic’ and ‘intragenesis or intragenic’ has been proposed. • Both more generally accepted by the public than the other techniques since they do not involve recombination between non-sexually compatible organisms. • No foreign sequences present in the final organism. ○ e. g selection marker genes & vector-backbone sequences

Cisgenic plants are those plants that have been genetically modified by one or more genes isolated from same species or from a sexually compatible one. In cisgenic crops, the donor gene and all regulatory sequences of transgene’s belong to the same crop species or belong to the host’s cross breedable species. In the cisgenic technology, the cisgene must be an identical copy of the host’s native gene cassette.

Intragenesis • Just like cisgenics, transfer of genes between crossable species. • However, unlike cisgenes, intragenes are hybrid genes. • ‘Intragenesis’ differs from cisgenesis in the composition of the genetic construct, as intragene is not a perfect copy of a natural gene • They composed of regulatory and coding sequences derived from the same species itself or from sexually compatible species but they can have genetic elements from different genes • by using different promoter or terminator regions, expression of genes can be modified.

P –DNA – plant derived transfer DNA