The unravelling
of the human genes viz. human genome project and the potential it provides has
accentuated the likelihood of human genomic editing. This has allowed
scientists to look into possible ways for restructuring the genes. Previously
this modification – even in humans – had been tried through selective breeding,
radiation, and DNA interpolation agent. These were methods of wholescale
editing and more so than often resulted in unwanted diseased traits and even
death. Recent advances in genomic editing techniques allow for precision and
possibilities.
Are evidences supporting Positive outlook ??
Zinc Finger
Nucleases (ZFNs), Transcription activators like effector nucleases (TALENs) and
the gene that has scientists most enthused Clustered regularly interspaced
short palindromic repeats (CRISPR) are some of the methods in and around which
lays the promise for future. CRISPR a family bacterial DNA along with enzyme
Cas9 acts like scissors and glue for cutting DNA at a specific point and
replacing it with a new sequence. This allows for treatment of mutations in
genes that cause disease. CRISPR-Cas technology has shown potential in the
treatment of cancer, hemophilia, cystic fibrosis, beta-thalassemia, infections,
and heart disease.
In 2016 FDA has
approved a clinical trial in which CRISPR would be used to alter T cells and
after engineering specific genes would be administered back into those same
people. Similarly, a trial that began in 2019 utilizes CCR5-modified CD4+ T
cells (using ZFN) for treatment of HIV infection. These trails are bound to make
an impact on what the future holds for human genetic engineering. But an even
bigger impact came in late 2018 when Lulu and Nana, Chinese twin girls, became
the first germline genetically engineered babies (Designer babies). The CCR5
genes of parental DNA had been modified such that these babies were resistant
to HIV infection.
Contradiction of Opinion and Ethical Dilemma
The scientific
world emblazoned with this advancement has searched for what the future might
hold for these babies. Was the genetic modification too early for these babies?
CCR5 modification in these twins might result in cancer due to off-target
effect and reduced lifespan. Also, research in mice with germline modified CCR5
shows that it may result in increased cognition and better recovery from
stroke. And speculations have been flying that this might be the case in these
babies as well. And the answer to this will come with time. Similarly, the
scientific community has raised concerns over whether or not there was even
CCR5 modification. Some pointing to only one gene modification in Lulu, thus
not acquiring HIV resistance and Nana being a genetically mosaic.
CRISPR-cas9
besides being used in a clinical scenario offers myriad of possibilities
especially when combined with preimplantation genetic diagnosis (PGD) allows
for selection of traits best suited for the baby or in an ethically
inconsiderate view – the parent. Promises of babies who are intelligent on par
with adults, who are beautiful and stay beautiful in adulthood by societal
standards, and who live on to be 150 without any disease or deformity bothering
them are some of the promises shown by this technology. Thus these babies are
colloquially termed as “designer babies”.
However, the
ethics surrounding “production” of these babies befuddles the ethics
surrounding human experimentation. The tenets of pricipalism - autonomy,
beneficence, non-maleficence, and justice – have to be ignored for these
experimentations. The possible instrumentalization of these babies is always of
concern. A concern in and around Kantian ethics which states that “a human
being can never be used as a means only and must be treated and end in itself”.
Similarly, with any experimentation, the issue of informed consent will always
be of concern. Also, the risk vs. benefits of such human experimentations without
prior knowledge of what these testing might result in is of concern. Lulu and
Nana if they knew they would have a shorter life span with the only benefit of
having resistance against acquiring HIV, probably would not have opted for
these experiments upon them.
lastly,
These ethical
concerns should and need to be answered before any human experiments are
carried out. The only possibility comes out of mapping phenotypic changes with
changing genotypes (reverse genetics). Similarly, this idea of having a child
with heightened phenotypic changes might also be a cauldron for heightened
societal disparity and social turmoil with the technology being availed to
certain influential and economically advantaged people.
Thank You !!!
Dr. Samyam Aryal
Thank You !!!
Dr. Samyam Aryal
