Linkage and Mapping in Eukaryotes

A series of vocabulary flashcards derived from lecture notes on linkage and mapping in eukaryotes, focusing on key concepts, definitions, and genetic processes.

Linkage

The tendency of genes located close together on a chromosome to be inherited together.

Chiasma

The point at which two homologous non-sister chromatids exchange genetic material during crossing over.

Recombination

The process by which genetic material is rearranged during meiosis, leading to the production of new allele combinations.

Map unit (mu)

A unit of genetic distance equivalent to a 1% chance of recombination occurring between two loci.

Testcross

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

Phenotypic Ratio

The ratio of different phenotypes produced by a genetic cross.

Parentals

Individuals showing the same traits as those of the P1 generation in a genetic cross.

Cis-configuration

A configuration in which one homolog carries both mutations and the other carries both wild-type alleles.

Trans-configuration

A configuration in which the mutations are on separate homologs and the wild-type alleles are also separated.

Recombinant Gametes

Gametes that have combined genetic material from both parents due to crossing over.

Independent Assortment

The principle that genes for different traits are inherited independently of each other.

Crossing over

The exchange of genetic material between non-sister chromatids during meiosis.

Drosophila

A model organism commonly known as the fruit fly, widely used in genetic studies.

Heterozygote

An individual having two different alleles at a locus.

Nonparentals

Offspring with phenotypes that differ from the parental generation due to recombination.

Expected Phenotypic Ratio

The ratio of phenotypes predicted by Mendelian genetics based on allele combinations in a cross.

Genotype

The genetic makeup of an organism, representing the combination of alleles for a given trait.

Homologous chromosomes

Chromosomes that are similar in shape, size, and genetic content.

Recombinant phenotypes

Phenotypes that result from the combination of alleles due to crossing over.

Alleles

Different versions of a gene that can exist at a specific locus on a chromosome.

P1 generation

The initial parental generation in a genetic cross.

Crossover event

An occurrence during meiosis when homologous chromosomes exchange segments, resulting in genetic variation.