Blog#46- 10/10/20
THE NEW MEANING OF LIFE
By
Richard Davis
This past week Emmanuelle Charpentier and Jennifer Doudna were awarded the Nobel prize in chemistry for their work on gene editing relating to something called CRISPR. In order to understand what CRISPR is requires a quick lesson in genetics.
CRISPR is an acronym for Clustered Regularly Interspaced Short Palindromic Repeats. But first the basics. Our genetic material is contained in 23 pairs of chromosomes found in each cell in our body. Half of each pair comes from each parent. Genes are the pieces of DNA inside the chromosomes that define the characteristics of an organism.
Here is a good practical definition of a chromosome from a dictionary web site. “The chromosome holds not only the genetic code, but many of the proteins responsible for helping express it. Its complex form and structure dictate how often genes can be translated into proteins, and which genes are translated. This process is known as gene expression and is responsible for creating organisms. Depending on how densely packed the chromosome is at certain point determines how often a gene gets expressed.”
Inside the chromosomes are strands of DNA that contain coded proteins. The sequence of the code determines what traits are expressed and passed on. In 1987 researchers noticed a recurring pattern on the DNA strand but they didn’t know why it was there or what its function was. It came to be known as CRISPR
Charpentier and Doudna and other researchers figured out that CRISPR and processes related to it allow sections of DNA to be altered. This is what gene editing is. Some believe that the information we have learned about CRISPR rivals the greatest changes in human society such as the printing press and the Internet.
CRISPR presents a host of ethical questions that society must deal with before gene editing progresses. Gene editing allows us to eliminate diseases. Scientists are currently working on eliminating the gene that causes Sickle Cell Disease. Some diseases are the result of a change in one place on one gene and those diseases, including Sickle Cell Disease, are ripe for elimination.
I urge people to learn more about how gene editing could affect future life. You don’t need to immerse yourself in the complex science of genetics. There are a number of good books that deal with the ethical implications of using the CRISPR technology to edit genes and we should become educated so that we can have a say in how this science progresses.
When scientists edit genes to eliminate disease or change characteristics they never know if there will be unintended consequences and that is something we have to keep in mind. It would be possible to kill off all of the mosquitos in world quickly using gene editing with the hope of eliminating all the diseases mosquitos spread, such as malaria. But we do not know what harm might come in a world without mosquitoes.
The big question in relation to gene editing is , “Should we do it just because we can?”
That is where informed world opinion comes into the picture. It is not just disease transmission that could be changed by gene editing. Gene editing could allow parents to pick from a menu of traits they want in a child and embryos could be edited to produce disease-free blue eyed children with webbed feet so they could become unbeatable Olympic swimmers.
Sadly, embryonic gene editing has already happened in China without approval from anyone. A scientist manipulated the genes in twin embryos of parents, one of whom was HIV positive, so the babies would not have the disease. He is now in jail but we have to figure out a way to control unethical scientists from using gene editing irresponsibly.
We will be hearing more about gene editing in the coming years and a little bit of education would go a long way to helping all of us make the best decisions possible while controlling the potential for harm.
I recommend this book for a basic introduction to CRISPR. It was written by a children’s book author and provides basic information for non-scientists without being too simplified. CRISPR: A Powerful Way to Change DNA by Yolanda Ridge and Alex Boersma