When engineering organisms and biological systems, we need to be able to change their genetic make-up. Genome editing is a field which is becoming more and more advanced all the time. Whereas once we could only make random DNA changes all over the genome, now the technology exists to change single bases at a precise location in genomes with millions or billions of bases. This section covers some of the ways in which genome editing can be achieved, as well as how DNA which has been edited can be inserted into an organism of choice.
DNA can be altered through a spontaneous process called mutation https://en.wikipedia.org/wiki/Mutation. Mutation occurs naturally during replication of DNA or via DNA damage and is responsible for all the diversity of life we see today. After all, if there was no way for DNA to change, all organisms on earth would have identical genomes and all look exactly the same. In this way, mutation is the driving force behind evolution.
Transformation (insertion) of new DNA into an organism may be enough to achieve the desired genetic modification. This method effectively works by adding new DNA into an organism, which results in the cell having an additional function. Transformation has historically been one of the main methods used to engineer cells.
- Gene Gun — A gene gun or a biolistic particle delivery system is a device for injecting cells with genetic information. The load is an elemental particle of a heavy metal coated with plasmid DNA. This technique is often simply referred to as bioballistics or biolistics. This device is able to transform almost any type of cell, including plants, and is not limited to genetic material of the nucleus: it can also transform organelles, including plastids https://en.wikipedia.org/wiki/Plastids.
- Nano Needle Injection — This amazing nanoinjector http://news.byu.edu/archive14-may-nanoinjector.aspx created at Brigham Young University can penetrate a cell wall and deliver DNA right inside. The clever device does this by drawing negatively charged DNA to its positively charged lance. It then penetrates a cell and reverses polarity, injecting the DNA in the process.
CRISPR is a bacterial immune system that has been repurposed as a precise molecular find-and-replace tool for genome editing. Dozens of variants of the CRISPR system exist, allowing scientists to find and modify any genetic element, in any cell, in any way. The applications of CRISPR genome editing are diverse as the tool lets researchers mutate any gene in order to elucidate its function, or modify a trait in an advantageous way.
- Applications of CRISPR — <div class="macroCard">
- How to use CRISPR - Basics
- How to use CRISPR - Advanced
- History of CRISPR
- CRISPR Topics to write about
- CRISPR Glossary
- Ethical implications of CRISPR
- CRISPR at the Molecular Level
- Statistics on CRISPR
A vector is a DNA molecule used as a vehicle to artificially carry foreign genetic material into another cell. A vector containing foreign DNA is called recombinant DNA https://en.wikipedia.org/wiki/Recombinant_DNA. Common to all engineered vectors are an origin of replication https://en.wikipedia.org/wiki/Origin_of_replication, a multicloning site https://en.wikipedia.org/wiki/Multiple_cloning_site, and a selectable marker https://en.wikipedia.org/wiki/Selectable_marker.