Linkage
Problems:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1. Dihybrid cross (corn)
Recessive alleles
Linkage
Recombination
Cis arrangement
Recombination frequency, map units
Using F2 progeny ratios to determine map units
Using map units to determine F2 progeny ratios
 
2. Dihybrid cross (FlyLab: forked and scalloped)
X-linked recessives in cis
Test cross vs sibling cross
Recombinants and parentals
Map distance
 
3. Dihybrid cross (FlyLab: forked and miniature)
X-linked recessive
Cis vs trans
3 two factor crosses to build map (forked, scalloped and miniature)
 
4. Dihybrid cross (FlyLab: spineless and incomplete)
Autosomal recessives
Test cross
No recombination in males
 
5. Trihybrid cross (FlyLab: miniature, singed, tan)
Gene order
Genetic map
 
6. Dihybrid, trihibrid cross (mice)
Autosomal dominant, autosomal recessive
Genotypes
Given map with three markers, predict number of F2 progeny