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The introduction with the thesis is the following:
Deoxyribonucleic acid or DNA is known to contain genetic information of human growth, performance and reproduction. As a result, one of the most important study fields for scientists has been manipulating DNA to prevent illnesses. Some people often disagree about human beings controlling nature. <u>However, there are several advantages why the study of DNA can imply significant advances to restrain dangerous diseases and improve the lives of human beings.</u>
An opinion essay introduction must include a thesis statement, which is underlined in the example. The thesis statement an idea that you must support with evidence in the next paragraphs, which in this case should consist of advantages of DNA to prevent serious human diseases.
