Genes pass on characteristics from parent to child. If you have red hair and your daughter also has red hair, it is because she inherited a specific gene. In simple terms, genes are sequences of DNA on chromosomes. Some genes are good, for example, passing on a talent for running. Other genes are bad and can cause health issues, such as a predisposition for some types of cancer. This is why scientists are continually looking for ways to change genes so that serious genetic diseases can be treated.
Gene editing is an important area of research, and it all began in the 1950s, with the discovery of the double helix structure of DNA. The ground-breaking work carried out by James Watson and Francis Crick pioneered the field of genetics and biology. In 1958, Arthur Kornberg successfully synthesized DNA in a test tube and later won the Nobel Prize for his work.
Work on Gene Splicing
Work in the field of genetics continued, and by 1971, Paul Berg pioneered gene splicing, using DNA from two different viruses. This proved it was possible to combine DNA from different molecules. In 1972, Recombinant DNA (rDNA) was created, whereby genetic material from one organism was introduced to another, paving the way for future genetic engineering experiments and gene editing as we know it today.
The Development of Genetically Engineered Drugs
By the 1980s, scientists were able to make genetically engineered drugs such as synthetic insulin, thus negating the need for animal-derived drugs. In 1986, the first recombinant vaccine was approved, and by 1988, genetically modified crops were grown, with varying degrees of commercial success.
More important milestones followed, including the cloning of Dolly the Sheep in 1996 and the first FDA-approved gene-targeted drug therapy in 2001.
The Development of CRISPR Gene Editing Tools
The development of CRISPR technology in 2012, by Jennifer Doudna and Emmanuelle Charpentier, was a game-changer and they were eventually awarded the Nobel Prize in Chemistry. CRISPR allowed scientists to make precise cuts to DNA. For example, DNA fragments associated with fighting infections can be snipped off and used to create a drug for a future infection.
Today, CRISPR technology is used to correct genetic defects, improve the resilience of genetically modified crops, and prevent the spread of disease. Scientists use CRISPR to find a specific piece of DNA in a cell. This can then be edited. More recently, CRISPR technology has also been used to switch genes on and off without changing the gene sequence.
CRISPR-Cas9 is a newer development and is a simple and versatile way to manipulate genes.
There is also Cas-CLOVER, which is an even cleaner CRISPR cell line engineering tool. This can target double-strand breaks to knock out and knock in genes and make base-pair edits. Cas-CLOVER technology is accessible for commercial applications and research and development.
Modern CRISPR gene editing tools are easy to use and highly specific. They have enabled patients with serious diseases such as sickle cell anemia to receive targeted therapies and find relief from pain.