Introduction
Genetic engineering as the process of identifying and isolating DNA from living or dead organisms and introducing it to a living cell (Protein engineering 2011). This process has been used in the production of human proteins such as insulin, which is used to manage diabetes type 1 and 2. The production of human protein is done through recombinant DNA technology (Insulin 2012). Recombinant DNA technology techniques are used to locate, isolate and amplify specific DNA strands.
In the production of human insulin, scientists use recombinant DNA technology to insert insulin DNA into bacteria, which under optimum environments multiply into numerous replicas containing insulin (Insulin 2012). Human insulin manufactured through this technique has been used by people suffering from Diabetes type 1 and 2, because their bodies do not produce the required amount of insulin needed to support normal bodily functions.
Despite the benefits derived from the production of genetically engineered human proteins, social issues such as scientists’ self-regulation, bioterrorism and anxiety surround genetic engineering of DNA have taken center stage for the last few decades (Abram et al, 1982). This paper shall set out to give a brief history of genetic engineering of human proteins. The process used to manufacture human insulin in laboratories shall be explained and various social issues that arise as a result of genetic engineering discussed.
Manufacturing of Human insulin: Historical overview
Manufacturing of human insulin has been existence since 1920’s (Ladisch & Kohlmann, 2008). Before 1900, people suffering from diabetes type 1had no chance of living healthy lives, because there was no medical intervention that could help them produce sufficient insulin. Frederick G. Banting and Charles H. Best were the first scientists to purify insulin from animal organs (Ladisch & Kohlmann, 2008).
Later in 1936, researchers produced a better version of insulin containing protamine (protein strand from fish sperm). One injection lasted for 36hrs because the body breaks down protamine slowly. In 1950, researchers were able to produce a better version of human insulin, which was faster and quickly assimilated by the body. Until 1980, human insulin was extracted from animals such as dogs, pigs and cattle (Insulin 2012). This was because the natural insulin from these animals was closely similar to that produced by human beings. However, insulin extracted from animals was not as efficient and it took longer to be processed by the body.
In addition, Insulin from animals had serious side effects on numerous people whose bodies rejected it (Insulin 2012). To address this issue, researchers put their efforts towards the production of insulin that mimicked the natural insulin produced by the human body. Efforts to create human insulin paid off in 1977 after a team of researchers discovered that insulin could be produced by inserting insulin genes into bacteria.
This process enabled the creation of recombinant bacteria capable of producing human insulin. In 1982 production of genetically modified human insulin was approved as a pharmaceutical product after Eli Lilly Corporation produced genetically engineered human insulin that did not require animal supplies. Since then, a large percentage of human insulin users use genetically modified insulin (CHANG et al, 1998).
Process used in the manufacturing of human Insulin
Insulin is made up of two amino acids chains that are separate but joined together by a disulfide bond (Human Insulin 2012). These chains are made up of different numbers of amino acids (21 for chain A and 30 for chain B). In the production of human insulin, scientists start of by growing these chains separately. Since the exact sequence of the insulin DNA is known, an amino acid sequencing machine is used to create the exact DNA of the chains. The two DNA molecules are inserted into plasmids. Afterwards, the plasmids are then inserted into the E. coli bacterium, which is harmless to human beings and can easily host this gene (Human Insulin 2012). The plasmids are then implanted into the E. coli bacterium next to its lacZ gene. This gene is preferred because it is easy to locate and cut. In addition, it is next to the amino acid methionine, which facilitates protein formation (Global diabetes community, 2012). Through the process of transfection, the newly formed plasmids enter the bacteria.
The bacteria are then placed in large sterilized fermentation vessels that holds a solution containing nutrients needed to support bacterial growth. This is done in order to facilitate replication of the bacteria containing the insulin chains. Assady et al (2012) assert that under this optimum environment, the genetically modified bacteria are allowed to grow and replicate through cell mitosis and that each replica contains the insulin gene.
After replication, the bacteria are split open and the resulting DNA undergoes purification process in order to isolate the insulin DNA from the remaining mixture. In most cases, the bacterium’s DNA is treated with a chain splitting reagent called cyanogen bromide (Assady et al, 2012). This process ensures that the insulin chains are separated from the rest of the DNA. Further testing is done to ensure that the insulin extracted is not contaminated (Assady et al, 2012).
The separated chains extracted from the bacteria are subjected to a reduction-reoxidation reaction. This process facilitates the creation of disulfide bonds which joins the chains together. The insulin batch is placed in a centrifuge device after being oxidized, in order to split the cells according to their size and density (Insulin 2012). Oxidizing agents are materials that cause the transfer of electrons (Insulin 2012).
After the bonding process, a purification process is undertaken to ensure that only insulin chains are left. Manufacturers test the insulin batches to ensure that there are no contaminants by using a marker protein that specifically detects the presence of the E. coli bacterium in DNA. Various chromatography and separation processes are conducted to test the viability of the extracted DNA (Making human insulin 2007). The process of manufacturing human insulin is done in a clean and optimum environment so as to minimize risks associated with contaminations.
Social issues raised by genetic engineering of human proteins
According to Abram et al (1982), the use of recombinant DNA technology has raised numerous social concerns from the scientists, public and governments across the world. Most of the issues raised have resulted from the fact that this life altering technology is left to the hands of a few people who may decide to use it in ways that puts millions of lives in danger. Genetic modification can be used to create bacteria containing dangerous diseases that may affect lives and the environment (Chapter 20 Molecular Genetics Lesson 3 – Genetic Engineering 2012. In addition, contamination during mass production may go unnoticed due to human or technical error, which would put many lives at risk. Abram et al (1982) reveal that there are people who believe that genetic engineering may cause irreversible mutations, thereby altering humanity as we know it.
Discussion and conclusion
Over the past few decades, genetic engineering has enabled scientists to come up with cheaper and safer ways of saving lives. In addition, it provides an avenue through which further research into other issues affecting mankind can be solved. For example, genetic engineering has been used in the development of drought resistant seeds and disease resistant plants among other. In regard to medical relevance, human insulin can be produced in large quantities and over a short period of time as a result of recombinant DNA technology (Assady et al, 2012). Consequently, Mass production of human insulin has ensured that people with different types of diabetes have a chance to live healthy lives (Abram et al, 1982). Despite the social concerns, there are rules and regulations that govern the processes used to manufacture human insulin to ensure safety.
This report set out to explore the role of genetic engineering in the production of human protein. The history and background of human insulin production has been offered and the process used in the manufacturing of the same discussed. The social concerns arising from the production of human insulin through genetic engineering have also been outlined. Despite the credibility of these issues, genetic engineering has proven to be an ally in our effort to facilitate our well-being. As such, more research should be done in order to find lasting remedies for other problems and care should be taken to ensure that the risks never outweigh the benefits.
References
Abram, M et al 1982, Splicing Life: the Social and Ethical Issues of Genetic Engineering with Human Beings. Web.
Making human insulin 2007. Web.
Assady, S et al 2001, Insulin Production by Human Embryonic Stem Cells. Web.
CHANG, S et al 1998, Human insulin production from a novel mini-proinsulin which has high receptor-binding activity. Web.
Human Insulin 2012. Web.
Ladisch, M & Kohlmann, K 2008, Recombinant Human Insulin. Web.
Insulin 2012. Web.
Protein engineering 2011. Web.
Chapter 20 Molecular Genetics Lesson 3 – Genetic Engineering 2012. Web.