Lecture 19 Non-Mendelian Genetics – part 1

These flashcards cover key concepts in Non-Mendelian Genetics, including definitions and explanations of complex genetic phenomena.

Multiallelism

The phenomenon where a gene has more than two alleles in a population, leading to multiple phenotypes.

Incomplete dominance

A form of inheritance in which the phenotype of a heterozygote is intermediate between the phenotypes of the two homozygotes.

Codominance

A genetic scenario where both alleles at a locus are fully expressed, resulting in a phenotype that displays characteristics of both alleles.

Pleiotropic alleles

Alleles that influence multiple phenotypic traits.

Epistasis

A genetic interaction where the expression of one gene is affected by the presence of one or more genes.

Dominant epistasis

A form of epistasis where the dominant allele of an epistatic gene masks the expression of all alleles of the hypostatic gene.

Recessive epistasis

A form of epistasis where a recessive allele of the epistatic gene suppresses the expression of the hypostatic gene.

Heterosis (Hybrid vigor)

The phenomenon where hybrids exhibit superior qualities or increased performance compared to their parents.

Penetrance

The proportion of individuals with a given genotype who actually express the associated phenotype.

Expressivity

The degree to which a genotype is expressed in an individual, leading to variability in phenotypes.

Quantitative traits

Phenotypes that result from the interaction of multiple genes and the environment, often following a normal distribution.