Recombinant DNA is also known as rDNA. To understand it fully, you need a basic knowledge of DNA. DNA is the keeper of all information needed to recreate an organism, and is composed mainly of four bases made of sugar, phosphate and nitrogen. The way these bases order themselves in your DNA determines your genotype, or your physical characteristics, those both seen and unseen. The four bases include:
A-adenine
T-thymine
G-guanine
C-cytosine
The different patterns of each of these bases make pairs and form the double helix that makes up the thousands of DNA strands that are in our bodies. These sequences don’t actually make up an organism, but the proteins contained in an organism. DNA is transcribed into mRNA, which is translated into the proteins that form an organism.
Recombinant DNA comes into being when a single piece of DNA is artificially combined with another strand of DNA. By combining two or more strands of DNA, scientists can create a new strand of DNA. The most common recombinant process is when you combine the DNA of two different organisms.
There are two main methods by which recombinant DNA is made:
Transformation- This is when you select a piece of DNA to be inserted into a vector and then cut that piece of DNA with a restriction enzyme. After that, the DNA inserts into the vector with DNA Ligase. This insert contains a selectable marker that allows for identification of the recombinant molecules. This is known as an antibiotic marker, and it is often used so a host cell without a vector will die when exposed to a specific antibiotic. Then, the host with the vector will become immune.
Non-Bacterial Transformation- This is a process which is equivalent to transformation except a phage is used instead of bacteria.
Recombinant DNA works when the host cell expresses a protein from the recombinant genes. There will be many recombinant proteins that will not be produced by the host unless expression factors are added. These depend on the gene being surrounded by a bunch of signals which provide instructions for the transcription and translation of the gene.
rDNA has been gaining importance over the last several years and will continue to gain importance in the future. These are some of the areas that it will influence:
Better crops (drought and heat resistance)
Recombinant vaccines (Hepatitis B)
Prevention and cure of sickle cell anemia
Prevention and cure of cystic fibrosis
Production of clotting factors
Production of insulin
Production of recombinant pharmaceuticals
Plants that produce their own insecticides
Gene Therapy
There are good and bad impacts of the further studies of DNA.
Good:
Improved medicines
Improved livestock (resistance to disease)
Improved crops
Prevent genetic diseases
Lower the cost of medicines
Safer medicines
Treatment for pre-existing conditions and diseases (cancer)
Bad:
Safety concerns
Environmental concerns
Ethical dilemmas over human and human embryo treatment
Today’s technology is advancing because of the insights and information found through rDNA. This advancement has advantages and disadvantages. Scientists must pick and choose how they want to use this valuable information.
By Jessica Maughan