Step 1: Understanding the statements.
Emphysema is a lung condition, and treatments are aimed at alleviating symptoms and improving breathing. The use of a DNase gene is not a common treatment for emphysema. Let's review the options.
Step 2: Analyzing the options.
(A) DNase gene is employed to treat emphysema: Incorrect — DNase gene therapy is used to treat cystic fibrosis, not emphysema. It helps break down the mucus in cystic fibrosis patients' lungs. Emphysema treatments typically focus on bronchodilators and oxygen therapy.
(B) Transgenic animals are used for the production of pharmacological compounds to treat PKU: Correct — Transgenic animals can be genetically modified to produce proteins or enzymes used in treating phenylketonuria (PKU).
(C) The investigation of new treatment of rheumatoid arthritis by transgenic animal is done: Correct — Transgenic animals are used in research to study new treatments for rheumatoid arthritis, including the development of biologic drugs.
(D) A vaccine is an antigenic preparation to induce immunity: Correct — This is a true statement. Vaccines contain antigens that stimulate the immune system to develop immunity against specific diseases.
Step 3: Conclusion.
The incorrect statement is (A) DNase gene is employed to treat emphysema. This is not a correct use of the DNase gene, which is used for cystic fibrosis treatment, not emphysema.