In a previous article I have presented the amazing developments that are occurring in the field of biology. Many of these developments are triggered by the growing understanding of the genetic structure of plants and animals, including human beings.
There are about 3 billion “letters” (molecules) that constitute the human genome. Amazingly it turns out 99% of these are identical in monkeys and human beings— about 2.985 billion of these are the same and the differences between us and monkeys lie in only 1% of the respective genomes. That may appear surprising to many, since the monkeys are significantly different from us in their physical appearance, dexterity of hands, intelligence, inability to speak etc. A part of the genome is responsible for the size of our brain, while other parts are responsible for our other physical features such as the ability to digest starch, use our hands for holding tools and for various behavior traits.
One of these traits is aggression. No other animal destroys its own species as mankind has done through the various wars in our history. We know for a fact that some persons are much more aggressive than others. In extreme cases, the aggressive tendencies lead to criminals indulging in violent crimes. Can we make the aggressive traits disappear by selective breeding? This has been done in animals and can be done in humans too. In an interesting experiment conducted in the Institute of Cytology and Genetics in Novosibirsk, Russia in 1970, mice were separated from one generation to the next and bred for aggressive and tame tendencies for 30 years. It was found that this resulted in two distinctly different groups of mice with amazing differences in their behaviour patterns. The tame group was extremely tame while that bred for aggressive tendencies was wild and ferocious. It is clear from these and a number of other experiments that certain genes are responsible for such behaviour in animals and humans. The answer to eliminating violent crime from our planet may therefore lie in making it mandatory for every criminal convicted for a violent crime to undergo a surgical procedure that would prevent him from having children and passing on the genes responsible for aggression to future generations. Over a period of time this could eliminate crime completely. So an understanding and application of genetics may finally lead to peace on earth!
Genetics may also have its impact in our leading longer healthier lives. Scientists working at Kings College London have identified certain genes that are responsible for the ageing process in human beings. They found that these genes are switched off and on by certain external factors such as diet and environment, and may hold the keys for living a longer healthier life. The discovery was made by Professor Tim Spector and Dr Jordana Bell after they examined the similarity and differences in the genetic make-up of several hundred twins of varying age groups. The scientists found that the four key genes that affected the rate of healthy ageing and potential longevity were related to cholesterol, lung function and maternal longevity. Their work opens the door to new anti-ageing therapies and provides a deeper insight into the ageing process.
Let us consider another trait — the ability of humans to talk, unlike other animals. What is responsible for giving humans this unique characteristic? Since a part of the genome is responsible for the development of that of the region of the mouth and larynx responsible for speech, it should be theoretically possible to create talking mice or monkeys. A “language gene” has been discovered when some British scientists were studying some members of the family that suffered with speech defects. The Oxford scientists found that the problem was caused by a defect in a particular gene (FOXP2 gene) that therefore became known as the “language gene”. With this information in hand, a group of German scientists led by Wolfgang Enard at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany have bred certain genetically modified mice that can make a human version of this gene. These mice showed a dramatic change in the way they made sounds. The gene was responsible for the coordination between the tongues, lips, larynx and lungs that is necessary for speech. The gene can also enhance brain functions so that ideas can be generated. So in time we may be able to develop talking cats, dogs, mice and monkeys – The Dr. Dolittle scenario may be actually played out in real life!
The understanding of genetics is also leading to the development of new weapons to fight disease. For example some 200 million people suffer from malaria each year and about 800,000 deaths are recorded annually due to malaria. The vast majority of these deaths (over 90%) occur in sub-Saharan Africa, and children are the most vulnerable. The disease is caused by the bite of a female mosquito. Dengue and yellow fever are also spread by the bites of mosquitoes. Anti-malarial drugs such as chloroquine are losing their efficacy because of the development of resistance. An exciting new approach to tackle malaria is to develop genetically modified mosquitoes. These have the potential to bring down the population of the harmful female variety. Scientists at the University of California Irvine, have been able to develop a genetically modified variety of these mosquitoes that prevents the female mosquitoes from flying. After the larvae have hatched on water, only the males fly away while the females cannot fly and therefore die. The males, carrying the mutation, can then mate with other females thereby propagating the “genetic defect” by passing it to the subsequent generations. Such an approach of “genetic genocide” can help to reduce the populations of malaria-causing mosquitoes and save millions of lives.
There are many advantages to breast feeding of babies by mothers as the amino acids (from which proteins are made up) as well as sugars, fats, enzymes, vitamins and minerals present in the milk of mothers are much more suited for the health of the babies, and facilitate the digestive process. The infection fighting antibodies present in the mother’s milk protect the baby from chronic and acute infections. However many mothers are unable to produce sufficient milk to breast feed their babies. Chinese scientists have now been able to produce genetically modified cows that can produce milk closely resembling human milk in its characteristics. This was accomplished by inserting human milk genes into cloned cow embryos which were then implanted into surrogate cows. The resulting calves born by this process were later able to produce milk closely resembling “human milk”!
In this amazing world of science where truth is oft stranger than fiction, genetics may lead to elimination of crime, healthier and longer lives, and new animal species that have certain desired characteristics genetically incorporated.
The author is the former Federal Minister of Science and Technology, former Chairman of Higher Education Commission and currently President of Pakistan Academy of Sciences