Ch 7 Flashcards
Genes are linked to
Linked genes do not
The closer two genes lie…
The degree of linkage can be used to
Chromosomes
Assort independently
The more often they are transmitted together
Construct Genetic Maps
Two sources of Recombination
Independent assortment of genes on different chromosomes
Crossing over for genes on the same chromosomes
Complete Linkage
Only nonrecombinant progeny are produced
Independent Assortment
Half of the progeny are recombinant; half are not
One cM =
1% recombinant progeny types
Map Distances Allow Predicting the Outcome of
Crosses Involving Linked Genes
The maximum recombination frequency is ___, no matter how far apart the genes
50%
For closely spaced genes (≤ 10 cM), the problem is _____, but for widely spaced genes, the problem becomes ____
insignificant
severe
Three things are combined in association mapping
A method for identifying genetic markers and their locations
Careful assessment of phenotypes
Powerful statistical methods to look for associations between particular haplotypes and the phenotype of interest
Linkage disequilibrium
means that particular pairs of alleles are associated
Linkage disequilibrium is the basis of
Linkage disequilibrium for a pair of alleles
genomewide association studies
decays over time.
Genomewide association studies look for associations between ____ and ____ within populations not in genetic crosses or families.
genes and molecular markers (linkage disequilibrium)
The alleles used for mapping markers are
single nucleotide polymorphisms
SNPs.
Haplotype
a set of particular alleles that is inherited as a group
Genetic maps are ____ but ____ tools for estimating the actual physical spacing of genes within the genome
useful but imprecise
