Submitted to and published by Biology-Online.org
(Modified) Question: Is the use of Genetically Modified Insulin for diabetics better than the alternative, natural animal insulin?
For the past 80 or so years, patients who have been suffering from all forms of Diabetes Mellitus, Type 1 or 2 have been able to treat their Diabetes with the use of insulin injections and supplementation. We learnt in Grade 11 that Diabetes is caused by either a lack of insulin production (Type 1) or an insulin resistance (Type 2). However, by means of physical insulin insertions, natural insulin levels are successfully maintained and, hence, are able to fulfil their role of monitoring and lowering glucose levels in the bloodstream. ["Insulin cannot be taken as a pill. The insulin would be broken down during digestion just like the protein in food. Insulin must be injected into the fat under your skin for it to get into your blood."] (Quote from Source 2) [1,2]
From 1921 until 1983, the only available ‘replacement' insulin is known as ‘Natural Human Insulin'. The insulin would be derived from the pancreases of cows and pigs, primarily, as well as, occasionally, fish and horses. Research on insulin preparation from these sources was still taking place when pharmaceuticals began selling it to the public. As a result, problems did occur, particularly early on, with patients experiencing allergic reactions to the injection of insulin. This was due to a lack in the purity of insulin that was being marketed, with other substances being included in production. By the 1970s, pharmaceutical companies guaranteed 99% purity of their insulin products, due to a process known as H.P.L.C. (High Performance Liquid Chromatography), which allowed Biochemists working on insulin to identify chemicals in a compound, such as their produced insulin. Separation and quantification of the various elements contributing to the synthesis of the compounds was also made possible, and in this way they could eliminate the impurities from their insulin products. However, as different patients have slightly different insulin needs depending on their individual body chemistry, ‘variations' of insulin are still offered, particularly depending on how quick the insulin needs to work. "Zinc suspension insulin is intermediate-acting insulin, taking 1 - 1.5 hours to work and lasting 24 hours, while insulin combined with zinc and promatine is longer-acting insulin, taking 4-6 hours but lasting 36 hours." (Quote from Source 6). [3,4,6]
Then, in 1983, Eli Lilly, a pharmaceutical company, first marketed what they termed ‘Synthetic Human Insulin'. These new insulin products were obtained with the use of Biotechnology, using recombinant DNA therapy. Producers believe that this production method reduces insulin impurities and, therefore, would reduce the number of cases of allergic reactions experienced by patients who would, before, have used natural insulin. The process of producing synthetic insulin is made by identifying, isolating and copying the insulin producing genes in a normal person. Then, using recombinant DNA therapy, the DNA of a host bacteria cell is prepared, before the human insulin gene is inserted into the bacterium's DNA plasmid. The plasmid is inserted back into the cell. Then, through DNA replication in the cell, the plasmids multiply within the cell. These cells are gathered, purified and, once able to produce proteins, are available for use in diabetics. (Process obtained from Source 5). As a result of its DNA modifications, "it is absorbed more rapidly and has a short more manageable duration of effectiveness... causes fewer allergic/autoimmune reactions than [normal] insulin". (Quote from Source 4). [4,5]
From this, one could believe that Synthetic Human Insulin is better and the way forward in modern medicine. Clearly, companies like Eli Lilly believe this is the case. It is reported that, in 1997, only ‘300 000 insulin users were on animal insulins'. (Quote from Scott King, Diabetes Health Magazine, from Source 9). Furthermore, in 2006, Eli Lilly announced a discontinuation of their animal insulin products, effectively forcing all of their consumers onto the genetically modified stuff (they are quoted as saying that supply for animal insulin had dropped below 1% in any case). [4,9]
However, during my research, it came to my attention that various users were not completely satisfied with the modern insulin. In particular, they have suggested that, while synthetic insulin reduces allergic reactions, it has been known to increase other side effects, particularly hypo-glycemia (basically, the insulin ‘overworks' and causes blood glucose levels to plummet, resulting in lack of glucose supply to the brain, causing problems as severe as seizures or comas). In one article I resourced, a female patient testified that, "While taking "human" insulin, my blood sugar control was poor. My blood test results were erratic and often differed from what I expected." (Quote from Source 10). She went on to say that, after changing to natural animal insulin, her "blood sugar control improved immediately". In a U.K. newspaper article, from The Guardian (I located the article online, as Source 7), talked about the ‘potentially-lethal' undocumented side-effects of ‘human' insulin. He conceded that there was no concrete evidence supporting this theory, but believed there is still merit in considering the minority of cases of side-effects that have been reported by users. The two cases exampled were that of individuals experiencing ‘blackout' and severe, uncontrollable aggression and rage. Another electronic source (Source 8) has listed, under the sub-heading ‘Facts', that, "GM synthetic ‘human' insulin causes side effects for some people that largely disappear with a change to natural animal insulin." (Quote from Source 8). The source continues, also acknowledging the occurrence of hypoglycaemia and noting, as I have discovered, there have been no large-scale experimental comparisons that have been conducted, comparing the two types of insulin. [7,8,9,10]
From this, I can, subjectively, conclude that natural animal insulin is the safer option for Diabetic patients. While synthetic insulin may work better, one cannot ignore the cases of side-effects, given their isolation. Therefore, I would suggest that a Diabetic patient should consider at least waiting for more information and available research regarding Synthetic Insulin before they use it. Of course, companies like Eli Lilly have made access to animal ‘insulins' more difficult.G.E.C