Genetics 3301

Chapter 16: Gene Function

Forward Genetics:

Ä Mutating wild type to generate mutants in all genes that have a particular phenotype; Choice of mutagen for general mutagenesis (16-3); Genetic selections versus genetic screens (16-4)

Ä Selecting Drosophila phototaxis mutants (16-7); Using zebrafish to screen for developmental mutants (16-12, 16-13); Screening for genes with a particular expression pattern using enhancer traps (16-14).

Reverse Genetics:

Ä Identifying mutations in a particular gene after random mutagenesis; Mutants that do not complement a deletion of the gene in question; PCR amplification of the gene in question for expected lesions depending on the mutagen used.

Ä Gene-specific mutagenesis; Targeted gene knockout (16-15); Site-directed mutagenesis to generate specific mutations for testing in vivo (16-16).

Ä Interfering with the expression of specific genes to produce a phenocopy; Inhibiting gene expression via RNA interference (RNAi) (16-18); Mechanism of RNAi (16-19).

Analyzing mutants from forward genetics:

Ä Recombination mapping and complementation analysis (16-21); Classifying mutant phenotypes - loss of function null or hypomorph and gain of function hypermorph or neomorph (16-22).

Key terms: Know all of these except chemigenomics, and repeat-induced point mutation (RIP).

Problems: 1, 6, 10, 12, 15, 16, 17, 19, 29, 32.