Introduction to Genetic Analysis

Flashcards covering key concepts from the lecture about genetic analysis and mapping methods.

Genome mapping

The process of determining the location of genes on a chromosome.

Recombination-based map

A genetic map based on the frequency of recombination between linked genes.

Physical map

A map that shows the actual physical distances between genes or markers on a chromosome.

Map unit (m.u.)

The distance between two linked genes where 1% of the products of meiosis are recombinant.

Centimorgan (cM)

A unit of measure for genetic linkage, equivalent to 1% recombination frequency.

Genetic recombination

Mixing of genes during gametogenesis that produces gametes with new combinations of genes.

Independent assortment

The distribution of alleles into gametes independently of one another.

Crossing over

The exchange of genetic material between homologous chromosomes during meiosis.

Test cross

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

Linkage

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

Dihybrid cross

A cross between individuals that differ in two traits.

Trihybrid cross

A cross between individuals that differ in three traits.

Cis linkage

When two dominant alleles are on the same homologous chromosome.

Trans linkage

When dominant alleles are on different homologs.

Chiasma

The point of crossover between chromatids of homologous chromosomes.

Prophase I

The stage of meiosis where homologous chromosomes pair up and crossing over occurs.

Sister chromatids

Identical copies of a chromosome joined together by a common centromere.

Chiasmata

The physical manifestations of crossover events between chromatids.

Heteroduplex DNA

DNA that contains strands from different homologous chromosomes.

Single nucleotide polymorphisms (SNPs)

Variations in a single nucleotide that occur at a specific position in the genome.

Restriction fragment length polymorphisms (RFLPs)

Variations in the length of fragments produced by restriction enzyme digestion of DNA.

Microsatellites

Short, repeating sequences of DNA, often used as molecular markers.

Polymerase chain reaction (PCR)

A technique used to amplify a specific DNA sequence.

Recombinant frequency (RF)

The proportion of recombinant offspring resulting from a genetic cross.

Molecular markers

DNA sequences that are associated with specific traits or alleles.

Double crossover

Occurs when two separate crossover events happen between the same pair of homologous chromosomes.

Interference

The phenomenon where one crossover event affects the likelihood of another crossover event nearby.

Huntington’s disease

A genetic disorder caused by mutations in the huntingtin gene.

Cystic Fibrosis

A genetic disorder caused by mutations in the CFTR gene.

Additive map distance

Total distance calculated by summing the distances between individual genes.

Recombination frequency calculation

Calculated as the number of recombinants divided by the total number of progeny.