Recall that Leber congenital amaurosis (LCA), a formof congenital blindness in humans, can be caused byhomozygosity for recessive mutations in the RPE65gene. Recently, a rare dominant mutation in RPE65has been implicated as one cause of an eye diseasecalled retinitis pigmentosa, which is characterized byretinal degeneration that can progress to blindness.The dominant RPE65 mutation is a missense mutation causing amino acid 447 in the polypeptide tochange from Asp to Glu. Little is known about thenature of the mutant protein.a. Do you think that the dominant allele is morelikely a loss-of-function or a gain-of-functionmutation? Explain.b. As described in this chapter, gene therapy for LCAhas been at least partially successful. Do you thinkthat the same kind of gene therapy can be used forpatients with retinitis pigmentosa caused by thedominant mutant allele of RPE65? Explain.

Recall that Leber congenital amaurosis (LCA), a formof congenital blindness in humans, can be caused byhomozygosity for recessive mutations in the RPE65gene. Recently, a rare dominant mutation in RPE65has been implicated as one cause of an eye diseasecalled retinitis pigmentosa, which is characterized byretinal degeneration that can progress to blindness.The dominant RPE65 mutation is a missense mutation causing amino acid 447 in the polypeptide tochange from Asp to Glu. Little is known about thenature of the mutant protein.a. Do you think that the dominant allele is morelikely a loss-of-function or a gain-of-functionmutation? Explain.b. As described in this chapter, gene therapy for LCAhas been at least partially successful. Do you thinkthat the same kind of gene therapy can be used forpatients with retinitis pigmentosa caused by thedominant mutant allele of RPE65? Explain.

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Description: Recall that Leber congenital amaurosis (LCA), a formof congenital blindness in humans, can be caused byhomozygosity for recessive mutations in the RPE65gene. Recently, a rare dominant mutation in RPE65has been implicated as one cause of an eye diseas

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 11QP: Two types of mutations discussed in this chapter are (1) nucleotide changes and (2) unstable genome...

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