Breakthrough in science?
THE HANS INDIA |
Feb 04,2018 , 02:16 AM IST
The alarming pace of discoveries which garnered momentum with the unravelling of the structure of DNA (Deoxyribonucleic acid) the basic blueprint of living organisms in the year 1953 has transformed Life Sciences. This phenomenal discovery besides cracking the fundamental unit of inheritance (genes), ignited the latent curiosity of manipulation of genetic material among scientists.
Incidentally, the collective efforts accelerated the genesis of a gamut of molecular biology techniques culminating in the evolution of new branch of study, Genetic Engineering which encompasses all the processes aimed at altering the genetic code of an organism. Till the 1970s, selective breeding was widely practised to manipulate genetic material. Initially, biomedical techniques like artificial insemination, in-vitro fertilisation (test-tube babies) were included under genetic engineering. The discovery of restriction enzymes in 1968, an indispensable tool for gene cloning accelerated the pace of genetic engineering.
Eventually, genetic engineering invariably refers to gene cloning. Cloning refers to the process wherein a target DNA (gene) is inserted into a circular piece of DNA or plasmid of a bacterium and generation of hundreds of identical copies of the gene. DNA cloning is used in the production of biopharmaceuticals, gene therapy and gene analysis. The term cloning became immensely popular when scientists at University of Edinburgh cloned the sheep Dolly in 1996.
In fact, Dolly had three mothers: one provided DNA, another egg and the third one was a surrogate mother. Using the technique of somatic cell nuclear technique (SCNT), the nucleus from the mammary gland is inserted into an unfertilised egg, whose nucleus was removed. This hybrid cell was implanted in a surrogate mother. The success of Dolly prompted scientists to use this technique for other animal species like dogs and pigs.
While cloned animals are widely hailed as symbols of scientific excellence, thefear creating designer babies and an army of clones began to haunt the scientific community. On January 24 China announced the creation two cloned monkeys Zhong Zhong, Hua Hua, the first primate clones developed with a technique similar to the one used in Dolly. To achieve this humongous feat, scientists at Institute of Neurology (ION) Shanghai made a few modifications.
They erased chemical modifications of DNA that potentially turn the embryonic cell into a specialised cell. Similarly, they used DNA from fetal cells and added a few factors to turn on genes responsible for embryonic development. They thus created 79 clone embryos and implanted them into 21 surrogate mothers and obtained two clones of long-tailed monkeys, Macaca fasicularis. Cloning primates are extremely arduous and have an abysmally low success rate.
Scientists across the world lauded their Chinese counterparts on their outstanding achievement who unabashedly expressed concerns that this technique might be used to clone humans. Besides humans, the subclass of primates (the big-brained mammals) includes monkeys, apes, lemurs, bushbabies and lorises. Allaying fears, scientists at ION clarified that they have created the clones to study genetic factors responsible for Alzheimer’s disease.
By creating a population of genetically identical monkeys’ scientists want to deactivate the genes responsible for causing diseases individually and study its effect. Besides, there is a huge demand for cloned monkeys to test drugs.
Primates have been preferred models for studying human mental disorders and degenerative diseases. Hundreds of monkeys are used to investigate Parkinson’s disease. Incidentally, genetic closeness and similarity make the study of primates significant and informative. Genome sequencing revealed that humans are 96 per cent similar to the apes. A section of scientists believes that the latest development is highly significant since SNCT technique can be used to save endangered animals.
Human cloning includes therapeutic cloning and reproductive cloning. Therapeutic cloning involves cloning of human cells or tissues for medical purposes like transplants while reproductive cloning is about making an entire clone of a human being.
Amidst burgeoning reports of production of various animal clones and rapid advancements in genetic engineering international community contemplated the possibility of elaborating a convention for addressing the concerns on human cloning. Accordingly, in 2005 UN General Assembly has adopted a declaration urging member states to prohibit all forms of human cloning “in as much as they are incompatible with human dignity and protection of human rights”. But the declaration was toothless since it was non-binding and owing to the ambiguity of wordings, countries failed to arrive at a consensus.
Compelled by the urgency to address the ethical concerns of cloning, countries began to urge UN for a binding treaty for prohibiting human cloning. As of now, countries are still divided with each country legislating its own laws. As of 2015, 70 countries are reported to have banned human cloning. The EU, Canada explicitly bans human reproductive cloning.
India doesn’t have a specific law on cloning. It allows therapeutic cloning and use of embryonic stem cells and issued guidelines banning reproductive cloning. The UK grants licenses to Universities for carrying out research on diabetes, Parkinson’s and Alzheimer’s Disease and permits research on human-animal hybrid embryos.
As of now, the US promotes stem cell research and development of pluripotent stem cell lines not involved in creating a human embryo. Although there are no federal laws banning human cloning completely, human reproductive cloning is banned in 15 states while three states prohibit the use of federal funds for the same.
With the development of primate clones, human cloning seems to have moved away from the realms of science fiction to a real possibility. Currently, certain sections of scientific community fervently back therapeutic human cloning for its potential benefits in organ transplanting. Similarly, childless heterosexual couples suffering from genetic disorders are pitching for reproductive human cloning.
Human cloning while offering a promise of ameliorating genetic disorders like cystic fibrosis, Down disease, Tay-Sachs disease can enliven slew of fictional realities of designer babies and genetic upgrades like smarter babies posing serious ethical concerns.
It is a tightrope walk. In absence of binding international concerns, nations are free to make their own legislation and issue guidelines to laboratories. The crux of regulating human cloning lies in strict enforcement. In any case, scientists must exercise discretion and shoulder the responsibility of defining their research activities for the betterment of
By: Ramaharitha Pusarla