Nature versus Nurture is a concept we start contemplating when we are young. The role our genetics have on our physical traits, our personality traits, and the development or possible development of illnesses (mental and physical) versus the role our environment has on these traits and illnesses is pondered often by Scientists and Researchers alike. Is it all coded into us, some sort of destiny in which we have no choices or ability to alter the outcome? Scientists have recently begun "connecting the dots"; determining the "risk variations" in genome sequencing in people with brain disorders such as Schizophrenia, Bipolar disorder, and Autism along with the biological processes in the brain that are affected by the genome variations. In a group of papers that have been shared by PsychENCODE researchers shared how they layered data from studying genetic markers at different points of development in postmortem brain samples to display the importance of genetic combinations at different points of development. There are 3 layers of data they collected that are important; the transcriptome, or total picture of gene expression that occurs when a gene is activated, the epigenetic profile which is the "record of how molecules—in this case, methyl groups (CH3)— attach to DNA in the genome, impacting the way genes are expressed", and histone modifications which are alterations of proteins that package DNA into the nucleus and determine whether or not a gene will be active or inactive at a point in development. These 3 layers of data allowed the scientists to study how the brain's development is affected by specific gene activity in different brain regions over time. The scientists further break down the layers of data to understand brain disorders; they studied a specific group of "co-expressing genes", a group they call ME37, and their activity in the late fetal development stage, just before birth. They found that this group of genes tend to be activated at the same time in neurons and undergo more changes than any other grouping of genes in the fetal brain. What is the most interesting part of this is that the team then noticed that a number of the genes in the grouping ME37 are considered "risk genes" for brain disorders such as Schizophrenia, Autism, Intellectual Disability and Neurodevelopmental Disorders. The study describes the "ME37 cluster in particular as being an area of risk for pathology and therefore one that is potentially rich in targets for future therapeutics." What kind of therapeutics are they referring to? Well, according to thegenehome.com, there are two types of gene therapy- a gene addition and gene editing. Gene addition is a process by which a functional or healthy copy of a gene is inserted into a person's cells by way of a vector. Essentially, the transgene or new gene is meant to perform an essential function and modify the effects of the mutated or non-functioning gene.
Gene editing is a process in which a gene is identified and the DNA sequence is broken in order to " insert new genetic material to override the faulty gene." Gene editing is currently in preclinical trials and its success is largely in relation to getting the specific gene directed to the correct cells.
The possibility of using gene therapy to eradicate diseases and disorders seems like a scientific miracle; clinical trials for curing previously incurable diseases such as HIV, Lung Cancer and leukemia are paving the way for testing and clinical trials on various other illnesses. In November 2018, it was reported (here https://www.technologyreview.com/2018/11/25/138962/exclusive-chinese-scientists-are-creating-crispr-babies/) that China had lept ahead, using the CRISPR technology to modify human embryos. The goal was to eliminate a gene called CCR5 which, in theory, should make the resulting offspring resistant to smallpox, HIV, and cholera. There was also speculation that a modification of the CCR5 gene would also lead to increased cognitive function, however, there hasn't been any progress report released on the twins that were born of this experiment.
The implications are two-fold; on the one hand, curing previously incurable diseases would certainly be a huge leap forward for science and man-kind. As science advances, we are able to identify and isolate the genes that cause or carry the physical and mental diseases and act to prevent them before any symptoms occur, leading to a healthier society as a whole. On the other hand, man-kind has a way of warping philanthropic ideas and inventions; concerns have been raised in the medical community as to whether or not we should be using gene editing and how it should be used and regulated in the future. For now, we can leave the debate up to those in the medical science community and continue our pursuit of the identification of the cause of Schizophrenia and the development of the cure.
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