5P: Genotype to phenotype Flashcards
Penetrance (P)
The probability of a genotype that will manifest the trait
- P(%)= clinically affected individuals/obligate carriers x100
When is penetrance typically variable?
In dominant inheritance -> causes trait to skip generations
An example of an autosomal disorder with incomplete penetrance
Polydactylyl (many fingers or toes)
Multiple allelism
There are more than three alleles of a gene in a population
only two of them may be in one individual
Complex heterozygosity
An individual who has two different mutant alleles at a locus
Allelic heterogeneity
Different alleles may cause same (similar) disease
Epistasis
- Describes how gene interactions can affect phenotypes
- When two different genes contribute to a single phenotype, those genes are said to be epistatic