What Is the Likely Mechanism by Which Repeat Expansions Cause

question 24

Multiple Choice

What is the likely mechanism by which repeat expansions cause myotonic dystrophy?

• A) Expression of polyglutamine sequences
• B) Repeat methylation and transcriptional silencing
• C) Translational silencing by the repeat
• D) Expanded repeats sequester excessive amounts of RNA-binding proteins
• E) C and D

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Definitions:

Short-Run

A period in which at least one factor of production is fixed, and firms can only partially adjust their output levels.

Long-Run Minimum Cost

The lowest cost at which a firm can produce any given level of output in the long run, when all inputs can be varied.

Average Total Cost Curve

A graph that shows the cost per unit of output at different levels of production, illustrating how average total cost changes with changes in output.

Short-Run

A period in which at least one of a firm's inputs is fixed and cannot be changed.