Suppose you initiate a screen for maternal-effect mutations in Drosophila affecting external structures of the embryo and you identify more than 100 mutations that affect these structures. From their screenings, other researchers concluded that there are only about 40 maternal-effect genes. How do you reconcile these different results?
To determine: The method in which one can resolve different results of maternal-effect mutations in Drosophila.
Introduction: A person initiates a screen for maternal-effect mutations in Drosophila which affects the external structures of an embryo. A person identifies more than 100 mutations that affect these structures. On the contrary, other researchers found that there are only about 40 maternal-effect genes.
Explanation of Solution
One can identify several different mutations or multiple alleles in some of the same genes. It may be possible that a person’s screen is more inclusive so that one can identify more subtle alterations than the screen of others. A person’s screen may have included some zygotic effect mutations, which depend on the action of maternal-effect genes.
Thus, different results of maternal-effect mutations in Drosophila can be resolved by identifying several different mutations on the same genes.
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Chapter 23 Solutions
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