Concept explainers
Suppose a particular gene is required for early development and also later for development of a particular tissue, such as the adult nervous system. By generating a homozygous mutant clone in that tissue of a heterozygote, researchers can circumvent the lethality that would result if the entire animal is homozygous for a loss-of-function mutation in that gene.
A technique called MARCM (Mosaic Analysis with a Repressible Cell Marker) was developed to enable Drosophila geneticists to generate homozygous mutant cell clones that are marked by the presence of a reporter protein such as GFP. Marker expression enables the investigator to observe clearly the mutant
a. | Diagram the chromosomes and the mitotic crossover that generate a homozygous m mutant clone marked by GFP expression. |
b. | How could you restrict the clones to the adult nervous system? |
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Genetics: From Genes to Genomes
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- Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning