Genes on the Same Chromosome: Linkage

These flashcards cover key vocabulary and concepts related to genetic linkage as discussed in the lecture.

Linkage

The tendency of alleles of different genes on the same chromosome to be inherited together.

Genotype

The specific allelic composition of a cell or organism.

Phenotype

The detectable outward manifestation of a specific genotype.

Recombination

A process that results in gametes with combinations of alleles not present in the parental generation.

Interchromosomal Recombination

Occurs through the independent assortment of alleles whose loci are on different chromosomes.

Intrachromosomal Recombination

Occurs through crossovers between loci on the same chromosome.

Parental Gametes

Gametes that retain their original combinations of alleles.

Recombinant Gametes

Gametes that have different combinations of alleles due to recombination.

Recombination Frequency (RF)

A calculation to define the number of parental and recombinant gametes, expressed as a ratio.

Coupling Configuration

When both mutant alleles are on one homologous chromosome and both wild type alleles are on the other.

Repulsion Configuration

When one wild type allele and one mutant allele are on one homologous chromosome, and the opposite is on the other.

Complete Linkage

A situation where two loci are so close together that the parental combinations of alleles always segregate together with a recombination frequency of 0.00.

Partial Linkage

Occurs when two loci are on the same chromosome but are far enough apart that crossovers may occur between them during some meioses.

Unlinked Genes

Genes that segregate independently, typically resulting in a recombination frequency of approximately 0.50.

Testcross

A cross between an individual with an unknown genotype and a homozygous recessive individual, used to determine the genotype of the former.