Genetic Recombination and Linkage Flashcards
What is the molecular basis for the law of independent assortment?
Genes act separately from one another during meiosis
What is a locus?
the position that a gene occupies in a chromosome or within a segment of genomic DNA
What are parental gametes?
those gametes produced by an individual that have the same genotype at the loci of interest as those of the gametes that formed the individual
What are recombinant gametes?
Those gametes produced by an individual that have a different genotype at the loci of interest from the gametes that formed in the individual
What is true about the parental and recombinant gametes according to Mendel’s second law?
They should be present in equal numbers
What does it mean if the recombinant genotypes occur in frequencies less than 25%?
Gene linkage is present
What are syntenic genes?
Genes on the same chromosome
What is complete (tight) linkage?
When genes are very close together on the same chromosome, no recombination occurs, and the parental genotypes are the only ones present in the gametes
What is linkage disequilibrium?
the nonrandom distribution into the gametes of a population of the alleles of genes that reside on the same chromosome
What is a haplotype?
the symbolic representation of a specific combination of linked alleles on a particular chromosome
What is coupling?
When the alleles of two genes that are on the same chromosome.
What is repulsion?
When the alleles of two genes lie on the homologous chromosomes
What is the fundamental concept of linkage analysis?
Partially linked genes have more recombination events the farther away they are from each other
What is a centimorgan?
Unit of measurement for recombination frequency
1 cM = 1% frequency of recombination
How does double recombination affect recombination frequency?
Makes it appear as a non-recombination event
