Humans have continually been fascinated with the inner workings of the human body; with particular focus on genetics and the potential outcomes of further study into this area. We’re so fascinated by it that in 1990 we decided to map the entire human genome which we completed in 2003; allowing for each gene and each variant of that gene to be recorded. This allows us to identify the sequence of nucleotides responsible for things like blue eyes, brown hair and a vast array of different phenotypes (physical characteristics).
Alterations of a persons ‘normal’ genetic sequencing or amounts via natural processes can result in a variety of conditions or diseases; trisomy of chromosome 21 (1 extra chromosome) leads to Down syndrome whereas a single deletion of 3 nucleotides (DNA structural unit) on chromosome 7 leads to Cystic fibrosis. As mentioned, this alteration of what is considered ‘normal’ is something that is natural with the process of meiosis (sex cell production) not being perfect all the time. In previous centuries, being born with a genetic disorder ended you up in “Freak Shows” where it was your purpose to scare and amaze viewers. If not, it resulted in a shortened lifespan due to complications associated with the disorder. For genetic diseases, some can be treated and the symptoms managed but there is a list of a few that result in certain death. What if this wasn’t the case?
That’s where CRISPR/Cas9 comes in. CRISPR stands for Clustered Regularly Interspaced Short Palindromic Repeats and Cas9 is the term given to CRISPR-associated genes. Normally, when a virus makes its way into a bacteria cell it will try to insert its DNA into it; this allows for it to be copied when its cells replicate themselves (repair and growth). When this happens, systems within the bacteria flags the area of the DNA where the foreign DNA has inserted itself; providing somewhat of an immunity to the foreign DNA. Using particular enzymes such as CAS9 (first enzyme of the system discovered), the area can be targeted and the foreign DNA removed from the normal DNA sequence; making it ineffective. The process was originally researched in 1993 and in June of this year, the technique originally used by bacteria is to be trialled in humans. The trial aims at using the CRISPR system to genetically alter immune cells to attack 3 forms of cancer.
This is a viable area of research because this system can be reprogrammed to target particular, incorrect sequences within a person’s genome; allowing for these incorrect DNA configurations to be removed and potentially repaired. This can lead to things like a cure for sickle-cell anemia, HIV and much more. There are many debates about the ramifications associated with the investment into CRISPR research and application; some say that this could lead to designer babies whereas some people say we’ve been doing this for years with selective breeding. Impressions and investment into CRISPR/Cas9 is continuing to increase as time progresses while some are still skeptical with the idea of permanently changing the human genome. Personally, I am indeed curious about where this technology might lead us but I think it still needs to be heavily monitored and regulated. There is still a lot of fear associated with CRISPR research and what it might lead to but deciding to ban it completely now before we’ve had a chance to properly utilize it is very foolish.
For an easy to follow and in depth video on CRISPR, have a look at Kurzgesagt – In a Nutshell.