2.4 How Alleles Alter Phenotypes Flashcards
What is gene interaction?
a single phenotype is affected by more than a single gene
What is a wild-type allele?
predominant allele in a population
How are alleles formed?
through genetic mutation
What is a neutral/silent mutation?
mutation that does not change the function or phenotype of a given gene
What is a loss-of-function mutation?
mutation that causes a partial or total loss of the function of a gene
What is a null allele?
mutation results in total loss of the genes function
What is a gain-of-function mutation?
mutation enhances the activity or function of the wild-type gene
What is an example of gain-of-function mutation that is not actually beneficial?
oncogenes
What is partial or incomplete dominance?
neither trait is truly dominant resulting in an intermediate phenotype
What are two examples of incomplete dominance?
Tay Sachs disease
Factor V
What is the threshold effect?
a minimum of gene product is needed to meet a normal phenotypic expression
