How do genetic mosaics help determine the focus of action of a gene?
A)Mosaics ae composed of cells with different genotypes so some genes may be active in some cells and not others.
B)Mosaics are created by mating flies are homozygous recessive for two different genes and the effects of the double miutations on the morphololgy of the progeny are studied.
C)Mosaics are created by mating two flies that carry homozygous gain-of-function muttions in different genes and the effects of the mutations on the morphology studied.
D)Mosaics are created by the Cre-loc system which allows for the deletion of specific genes at controlled stages of development.

Question

Quizplus · Accepted Answer

Genetic mosaics are organisms that have cells with different genotypes due to mutations or genetic alterations that happened after the fertilization of the egg. By observing the phenotype of the different cells, researchers can determine which genes are active in which tissues or organs. This enables them to understand the focus of action of a gene, i.e., where and when it is expressed and what its specific function is. By comparing the mosaic pattern with the normal phenotype, researchers can infer how mutations affect development and gene expression. Therefore, option A is the best choice because it describes how mosaics can be used to study the expression and action of genes in specific tissues or cell types. Options B, C, and D describe other strategies that can be used in genetics research but are not directly related to genetic mosaics.

How Do Genetic Mosaics Help Determine the Focus of Action