Which of the following is not caused by over expression of a trinucleotide repeat?
High-Yield Explanation
Ans: a (Alzheimer's disease) Ref: Ganong, 22nd ed, p. 215Alzheimer's disease is not caused by over expression of a trinucleotide repeat. The rest 3 options are examples of trinucleotide repeat diseases where as Alzheimer's is primarly a degenerative disease (Basal ganglia) resulting in movement disorder.Some examples of trinucleotide repeat diseases:-Huntington's disease -- CAGSpinocerebellar ataxia --CAG(Type 1, 2, 3, 63)Fragile X syndrome -- CGGMyotonic dystrophy -- CTGFrederich's ataxia -- GAA