Multiple Allele Crosses
e.g. 3 blood types:
- IA = Blood group A (dominant)
- IB = Blood group B (dominant)
- 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