As shown in Figure 14.1, mutations in the Drosophila Ultrabithorax (Ubx) gene result in wings developing from two thoracic segments, rather than just one as in wild-type flies. In the mouse genome there are two Ubx orthologs (see Genetic Analysis 14.2 for definition). How would you determine whether the two mouse genes have distinct or redundant functions?

Key Concepts

Gene Orthologs

Gene orthologs are genes in different species that evolved from a common ancestral gene through speciation. They typically retain the same function across species, making them crucial for comparative studies in genetics. Understanding orthologs helps researchers infer the evolutionary relationships and functional similarities between genes in different organisms, such as the Ubx gene in Drosophila and its counterparts in mice.

Gene Function Analysis

Gene function analysis involves experimental approaches to determine the roles of specific genes in an organism. Techniques such as gene knockout, where a gene is deliberately inactivated, or gene overexpression can reveal whether genes have distinct or redundant functions. By observing phenotypic changes in organisms lacking one or both genes, researchers can assess the functional contributions of each gene.

Mutational Analysis

Mutational analysis is a method used to study the effects of specific mutations on gene function and organismal phenotype. By introducing targeted mutations in the mouse Ubx orthologs, researchers can observe any resulting changes in development or morphology. This approach helps to clarify whether the two genes perform unique roles or if they can compensate for each other’s functions in the absence of one.