Gene Linkage and Recombination

linked genes

gene alleles that are close together on the same chromosome

tendency to be inherited together 

can be used to identify genes

linkage group

all the genes on a chromosome

parental

gametes that contain the same combination of alleles as the original chromosomes

recombinant

gametes that contain a new combination of alleles that results from crossing over during meiosis

closer

the closer/farther genes are, the rarer the crossover events between them 

50%

what is the highest percentage of recombinants possible for all cases?

cis

genes are on the same chromosome

trans

genes are on different chromosomes

phasing

determining which variants are from the same copy of a chromosome and which are from different copies of a chromosome

number of recombinants/total number of offspring

recombination frequency equation

some meioses are ncos

the recombination frequency is less than 50 when

no meioses are ncos

the recombination frequency is equal to 50 when