Wonders of biotechnology

Wednesday, May 22, 2024

Biotechnology is a fascinating and wondrous field of science that has continued to evolve by leaps and bounds, particularly after the unravelling of the structure of DNA in the 1950s.

Biotechnology involves the use of living organisms or their derivatives to create products and processes for specific uses. The field has seen significant advancements over the past few decades. Its applications span numerous sectors, but its impact on agriculture and health is particularly profound.

A huge boost to this field was given in Pakistan when I was the federal minister of science and technology during 2000-2002. The National Commission of Biotechnology was set up, and eminent biotechnologist Dr Anwer Naseem was appointed to head it. Several projects were funded under the auspices of the commission, resulting in an exponential increase in scientific publications in biotechnology-related fields from Pakistan.

Centres such as the National Institute of Biotechnology and Genetic Engineering (NIBGE) and the Nuclear Institute for Agriculture and Biology (NIAB) Faisalabad, operating under the Atomic Energy Commission, have played a valuable part through development of improved varieties of cotton, wheat and other crops utilizing biotechnology tools.

Let us try to understand some aspects of this very important field. DNA, or deoxyribonucleic acid, is the molecule that carries the genetic instructions for life. Imagine it as a long, twisted ladder made up of four types of building blocks (molecules), which can be thought of as letters. These ‘letters’ form the ‘words’ and ‘sentences’ that tell our cells how to function, grow, and reproduce. There are some three billion ‘letters’ in human DNA.

Just as a recipe tells a cook how to make a dish, DNA provides the blueprint for making all the proteins and structures that our bodies need. It is found in almost every cell of our body and is passed from parents to children, determining everything from our hair colour to our risk for certain diseases. Essentially, DNA is the biological code that makes each living thing unique and keeps life going.

Genetic engineering is a cornerstone of agricultural biotechnology, involving the manipulation of an organism’s DNA to achieve desirable traits. This technique has led to the development of genetically modified (GM) crops, which offer numerous benefits. For instance, Bacillus thuringiensis (Bt) corn and cotton are engineered to express a bacterial toxin that is lethal to certain insect pests, reducing crop losses and increasing yields.

Another example is the development of pest and disease-resistant GM crops, such as virus-resistant papaya, which has significantly revived papaya production in Hawaii. Similarly, herbicide-tolerant crops like Roundup Ready soybeans are modified to withstand specific herbicides, allowing farmers to control weeds without damaging the crops, leading to more efficient weed management and reduced labour costs.

Additionally, biotechnology enables the enhancement of the nutritional profile of crops. Golden Rice, for example, is engineered to produce beta-carotene, a precursor of vitamin A, addressing deficiencies in populations that rely on rice as a staple food. Furthermore, biofortified crops such as iron-enriched beans and zinc-enhanced wheat have been developed to combat malnutrition in developing countries.

Molecular markers are parts of DNA associated with specific traits and they are used in marker-assisted breeding (MAB) to accelerate the development of new plant varieties with desirable characteristics. This technology significantly improves breeding efficiency by allowing the selection of plants with desired traits at the seedling stage, thus reducing the time required for breeding programs.

For example, rice varieties with enhanced drought tolerance and disease resistance have been developed using molecular markers. Molecular markers can also identify disease resistance genes, enabling the development of resistant crop varieties more efficiently than traditional methods. For instance, wheat varieties resistant to rust, a devastating fungal disease, have been developed through MAB, significantly reducing crop losses.

A technology that allows rapid multiplication of plants involves ‘tissue culture’. Plant tissue culture involves the cultivation of plant cells, tissues, or organs under sterile conditions on a nutrient culture medium. It enables the rapid multiplication of plants with desirable traits, producing genetically identical clones. This is particularly valuable for crops like bananas and orchids, which are propagated vegetatively.

Biofertilizers and biopesticides are derived from natural sources and utilize biological processes to enhance soil fertility and control pests. Biopesticides, derived from natural materials like plants, bacteria, and certain minerals, offer a sustainable alternative to chemical pesticides.

Bacillus thuringiensis (Bt) is a widely used biopesticide that produces toxins harmful to specific insect pests but safe for humans and beneficial insects. Other examples include neem oil, extracted from the neem tree, which has broad-spectrum insecticidal properties, and trichoderma, a fungus used to control soil-borne diseases.

Turning to applications of biotechnology in health, the field of genetic engineering has been employed for correcting genetic disorders and developing advanced therapeutics. Gene therapy involves the introduction, removal or alteration of genetic material within a patient’s cells to treat or prevent disease. For example, spinal muscular atrophy (SMA) has been treated using gene therapy.

Another promising application is the use of gene editing technologies like CRISPR-Cas9, which allows precise modifications to the DNA sequence. This technology may eventually be used for treating genetic disorders like cystic fibrosis or sickle cell anemia. CRISPR has also been used to develop innovative cancer therapies, where immune cells are genetically modified to better recognize and attack cancer cells.

Biotechnology has transformed vaccine development, making it possible to create safer and more effective vaccines. A significant advancement is the development of mRNA vaccines, which use synthetic mRNA to instruct cells to produce the viral antigen. The Covid-19 pandemic highlighted the potential of mRNA vaccines, such as those developed by Pfizer-BioNTech and Moderna, which were developed and scaled rapidly.

Stem cell therapy, another branch of biotechnology, aims to restore function to damaged tissues and organs. It is a promising approach, as stem cells have the potential to differentiate into various cell types. This offers treatments for conditions like spinal cord injuries – where stem cells can potentially regenerate damaged neurons – and heart disease, where stem cells can help repair damaged cardiac tissue.

Biotechnology enables the development of bioengineered organs and tissues for transplantation, potentially addressing the shortage of donor organs. Examples include bioengineered skin for burn victims and lab-grown bladders that have been successfully implanted in patients.

While the applications of biotechnology in agriculture and health offer numerous benefits, they also raise ethical and societal concerns. The safety and environmental impact of GM crops remain contentious, with concerns including the potential for allergenicity, gene flow to wild relatives, and the development of resistant pests and weeds. The use of CRISPR and other gene-editing technologies in humans raises ethical questions about genetic modifications, potential unintended consequences, and the possibility of ‘designer babies’.

The writer is a former

federal minister, Unesco

science laureate and founding

chairperson of the Higher

Education Commission (HEC). He can be reached at: