Multiple Allele Crosses

e.g. 3 blood types:

  1. IA = Blood group A (dominant)
  2. IB = Blood group B (dominant)
  3. Io = Blood group O (Recessive)

Dihybrid Crosses

  • The inheritance of two characteristics which are controlled by different genes
  • Each of the two genes will have different alleles
  • Dihybrid crosses can be used to determine the likelihood of offspring inheriting certain combinations of the two characteristics from particular parents
  • A dihybrid cross for two heterozygous parents leads to a 9:3:3:1 phenotypic ration