Final answer:
The first genetically modified microorganism to be patented was used for producing human insulin to treat diabetes, marking a significant advancement in recombinant DNA technology and the treatment of diabetes.
Step-by-step explanation:
The first genetically modified microorganism that was granted a patent was for producing a human protein used to control blood sugar levels. This breakthrough was made possible through recombinant DNA technology, which was used to produce large-scale quantities of human insulin in E. coli.
Prior to this, diabetes was treated with pig insulin, which could cause allergic reactions in patients due to differences in the gene product. However, since 1978, genetically engineered E. coli could produce human insulin, providing a more effective and consistent treatment for those with diabetes.