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denotes linked genes TERM 2
coupling configuration
DEFINITION 2 dominant (or wild type) alleles of two linked genes are present on the same homolog cis TERM 3
repulsion configuration
DEFINITION 3 dominant (or wild type) alleles of two linked genes are present on different homologs trans TERM 4
segregation of linked genes during meiosis
DEFINITION 4 recombination (crossing over) can occur between non-sister chromatids TERM 5
recombination frequency
DEFINITION 5
recombinants/#total progeny X 100
Using a chi-square test to determine linkage
for linkage studies, the null hypothesis is that there is no linkage, i.e. there is independent assortment if P < 0.05, the hypothesis of independent assortment can be rejected TERM 7
df
DEFINITION 7 = (# of rows - 1) x (# of columns - 1) TERM 8
Frequencies of gamete classes in
trihybrids
DEFINITION 8 when 3 genes are linked, each of the 6 recombinant gamete classes are produced at frequencies significantly lower than that predicted by chance within each crossover, both gamete types that result are equally frequent double crossover classes are the least frequent because both crossover events must occur TERM 9
Steps in determining gene order in a 3 point
cross
DEFINITION 9 Identify the NR progeny (2 most numerous phenotypes) Identify the DC progeny Compare the phenotype of the DC with the NR. They should be alike in 2 characteristics and differ in one The characteristic that differs between the DC and NR is encoded by the middle gene ` TERM 10
Frequency of the DCOs
DEFINITION 10 always is much less than the frequency of SCOs product rule of each of the SCOs
