Linkage Analysis Flashcards
What is linkage?
tendency for genes or segments of DNA closely positioned along a chromosome to segregate together at meiosis and therefore be inherited together
What is linkage analysis?
indirect DNA analysis. The use of several DNA markers that are near or within a gene of interest to track within a family the inheritance of disease-causing mutations
What is a marker?
an identifiable segment of DNa with enough variation between individuals that its inheritance and co-inheritance with alleles of a given gene can be traced
What is a phase?
for two or more closely linked markers, the alleles contained on the same chromosome; haplotype
What is linkage disequilibrium?
co-occurence of specific alleles at a higher frequency than would be predicted by random chance; over-representation of specific haplotypes
What is haplotype analysis?
molecular genetic testing to identify a set of closely linked genes in DNA
What can mess up linkage analysis?
recombination. This is why you should aim to use tightly linked markers or ones in linkage disequilibrium
Can you perform linkage analysis without family history?
no. linkage analysis always requires a pedigree. Can start tracking for future generations if no history available.
Is linkage analysis every 100% sure?
never. always a risk of innaccuracy because of recombination
What is the effect of a homozygote on linkage analysis?
it makes it inconclusive because you don’t know if recombination occurred or not.
