If genes can be transplanted from animals to humans, why can’t the gene that produces insulin be transplanted from an animal to a patient with diabetes for a cure?
Some studies have shown that expression of the insulin gene through a modified virus is able to revert diabetes in rats. Whether this approach could work in humans remains to be determined, because rats maintain glucose levels differently than humans.
One of the major problems in this type of therapy is modulating the expression of the exogenous insulin gene introduced in an individual. The production of endogenous insulin is tightly controlled by a fine mechanism that depends on circulating glucose levels. When blood glucose levels are high, insulin is secreted; when they are low, insulin is not secreted. When the exogenous insulin gene is introduced, it is very difficult for an organism to regulate the normal physiology of its transcription, which may result in excessive, and life-threatening, production of insulin. However, this type of therapy is one of the novel strategies being investigated for the cure of diabetes.
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