Huntington’s disease is an inherited neurological ailment with a variable age of onset. A protein called huntingtin has a sequence of repeated glutamine residues, all encoded by CAG. The number of repeated CAG triplets is expanded in Huntington’s disease, apparently as the result of replication errors. The age of onset is related to the number of CAG triplets in the repeat region; the more glutamine codons, the earlier the onset. Describe experimental evidence, using Southern blotting, that is consistent with this finding.

Huntington’s disease is an inherited neurological ailment with a variable age of onset. A protein called huntingtin has a sequence of repeated glutamine residues, all encoded by CAG. The number of repeated CAG triplets is expanded in Huntington’s disease, apparently as the result of replication errors. The age of onset is related to the number of CAG triplets in the repeat region; the more glutamine codons, the earlier the onset. Describe experimental evidence, using Southern blotting, that is consistent with this finding.

Human Heredity: Principles and Issues (MindTap Course List)

11th Edition

ISBN:9781305251052

Author:Michael Cummings

Publisher:Michael Cummings

Chapter11: Genome Alterations: Mutation And Epigenetics

Section: Chapter Questions

Problem 10QP: If the coding region of a gene (the exons) contains 2,100 base pairs of DNA, would a missense...

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Huntington’s disease is a hereditary central nervous system disorder characterized by tandem repeats of the sequence 5'-CAG-3' in the gene that encodes a protein called huntingtin. The disease is progressive from generation to generation, meaning that in later generations the number of CAG repeats increases and the age of onset of symptoms decreases. Refer to Figure 21.4 and describe the sort of evidence supporting the generational increase in the number of CAG repeats.