Human genomic DNA consists of more than 3 billion base pairs that could be visualised as letters which encode information. If any one letter is modified, a person falls ill. If we want to help a person recover, we should cut out “bad” DNA letters and replace them with the “good” ones in order to restore the functioning of normal biological processes. However, this technology is sophisticated and not easy to control; it requires particularly accurate tools – kind of DNA scissors. Scientists have been searching for ways to make these scissors as accurate as possible so that the process of cutting and replacement of DNA sequences is made easier and simpler.
“With our previous tools, it was either impossible or very difficult or very costly. Our technology enables the use of Cas9 proteins as molecular scissors, whereas DNA is recognised by the RNA molecule. After we modify it, we can refer the protein exactly where we want it to be. This technology will particularly accelerate and cheapen the DNA cutting processes,” says Dr. Giedrius Gasiūnas, a scientist at the Institute of Biotechnology of Vilnius University.
The gene editing technology which he developed together with his colleagues Prof. Dr. Virginijus Šikšnys, Dr. Tomas Šinkūnas and Dr. Tautvydas Karvelis has caused a great stir in the scientific community. It opens an opportunity to cure genetic diseases, i.e. target at the particular spot of genome which causes an illness and rectify it.
“Our ultimate aim is to help a person recover or alleviate his condition. Currently, people who are ill with genetic diseases might only combat their effects or alleviate the symptoms, instead of eliminating their causes. This technology will do it,” says Dr. Gasiūnas.
According to him, the new technology opens a way to other scientific research as well. Human genome contains around 20,000 protein-coding genes. However, we still lack knowledge of them. If we are able to turn off, turn on or relocate proteins, we could understand their functioning and better know their mechanisms.
“There has been quite a stir among scientists when they found out that theoretically we can not only cure genetic diseases, but also edit human embryos. The scientific community has been organising conferences on ethical and regulatory issues and has been discussing whether people have the right to do this and if yes, in what cases,” adds Dr. Gasiūnas.
The technology developed by Lithuanians might also be applied in agriculture. As we know, humankind seeks to discover more effective plant species that require fewer fertilizers or chemicals. The process of derivation of new species has so far been quite long and mutations have been random, whereas the new technology would enable their purposeful formation without any unnecessary modifications.
“In other words, no additional DNA would be inserted in the cell. At present, the United States of America have approved and the European Commission has been discussing the fact that such plants are not considered to be genetically modified. Their DNA would remain the same, yet their nutrient profiles would considerably improve and they would require fewer fertilizers or chemicals,” explains the scientist.
Scientists are hesitant to forecast how quickly these technologies will be applied in practice. Adaptation, in particular for curing diseases, is a very long process, since all medications have to pass through several phases of clinical trials.
“A lot depends on the success of these technologies. Clinical trials have already been started in the USA and China, where these technologies are applied in the treatment of certain types of blood cancer. When these technologies are applied in Lithuania will depend on their development and, certainly, their price and availability,” says Dr. Gasiūnas.
The scientists of the Institute of Biotechnology of Vilnius University – Dr. Gasiūnas, Prof. Dr. Šikšnys, Dr. Šinkūnas and Dr. Karvelis – have been nominated and awarded the Lithuanian Science Award for the cycle of works CRISPR-Cas System Research: From the Bacterial Defence System to the Gene Editing Technology.