The Normal Gene for Hemoglobin Was Isolated, Cloned, and Subjected

question 11

Multiple Choice

The normal gene for hemoglobin was isolated, cloned, and subjected to restriction enzyme digestion with BamHI. Following gel electrophoresis, three bands are routinely obtained. However, following the same procedure with the hemoglobin gene from an individual with sickle cell anemia, four bands are routinely obtained. These data suggest that

• A)the assay was not performed correctly.
• B)the mutation associated with sickle cell anemia results in DNA that breaks easily.
• C)the mutation associated with sickle cell anemia results in the loss of a BamHI cut site.
• D)the mutation associated with sickle cell anemia results in several new enzyme cut sites for a variety of restriction enzymes.
• E)the mutation associated with sickle cell anemia results in the gain of a BamHI cut site.

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Definitions:

Epidermis

Outermost tissue layer. In animals, the epithelial layer of skin. In plants, the dermal tissue.

Mesoderm

Middle tissue layer of a three-layered animal embryo.

Ectoderm

Outermost tissue layer of an animal embryo.

Implantation

The process by which a fertilized egg attaches itself to the lining of the uterus, marking the beginning of pregnancy.