Who constructed the first artificial recombinant DNA molecule in 1972?

Options

A. Collins and Holin
B. Stanley Cohen and Herbert Boyer
C. Arber, Nathan and Smith
D. Paul Berg and Barbara Wilkins

Answer

To answer the question of who constructed the first artificial recombinant DNA molecule in 1972, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Scientists Involved**: The first step is to recognize the key scientists who were involved in the creation of the first artificial recombinant DNA molecule. According to the information provided, the scientists are Stanley Cohen and Herbert Boyer.

2. **Understand the Context of Their Work**: Stanley Cohen and Herbert Boyer conducted their experiments using the bacterium Salmonella typhimurium, which is known to cause typhoid fever. This context is important as it highlights the significance of their work in the field of genetics.

3. **Define Recombinant DNA Technology**: Recombinant DNA technology involves combining DNA from different organisms. In 1972, Cohen and Boyer successfully created the first artificial recombinant DNA molecule, marking a significant milestone in biotechnology.

4. **Differentiate from Other Scientists**: It’s essential to differentiate Cohen and Boyer’s work from other scientists mentioned, such as Paul Berg and Barbara McClintock, who also contributed to the field of recombinant DNA but were not the first to create an artificial recombinant DNA molecule.

5. **Conclusion**: Based on the above points, we conclude that the first artificial recombinant DNA molecule was constructed by Stanley Cohen and Herbert Boyer in 1972.

### Final Answer:
Stanley Cohen and Herbert Boyer constructed the first artificial recombinant DNA molecule in 1972.

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