Concept explainers
Parkinson disease causes rigidity, tremors, and other motor symptoms. Only 2% of cases are inherited, and these tend to have an early onset of symptoms. Some inherited cases result from mutations in a gene that encodes the protein parkin, which has 12 exons. Indicate whether each of the following mutations in the park in gene would result in a smaller protein, a larger protein, or no change in the size of the protein:
a. Deletion of exon 3
b. Deletion of six consecutive
c. Duplication of exon 5
d. Deletion of intron 2
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