Backcross
From WikiLectures
This article was checked by pedagogue
|
This article was checked by pedagogue, but more than year ago. Signature: Prof. Ondřej Šeda, M.D., Ph.D. (talk) |
Backcross (Bc) refers to mating of heterozygous F1 generation individual with the homozygous parental generation individual. In the presence of complete dominance (A > a), the following genotypic and phenotypic ratios can be found in the Bc generation:
Monohybridism (single locus / gene, two alleles)[edit | edit source]
Bc – Monohybridism:
- Aa x AA
Genotype ratio: 1 (AA) : 1 (Aa)
Phenotype ratio: uniform
- Aa x aa
Genotype ratio: 1 (Aa) : 1 (aa)
Phenotype ratio: 1 (Aa) : 1 (aa)
Dihybridism (two loci / genes with two alleles each)[edit | edit source]
Bc – Dihybridism:
- AaBb x AABB
Genotype ratio': 1 (AABB) : 1 (AABb) : 1 (AaBB) : 1 (AaBb)
Phenotype ratio: uniform
- AaBb x aabb
Genotype ratio: 1 (AaBb) : 1 (Aabb) : 1 (aaBb) : 1 (aabb)
Phenotype ratio: 1 : 1 : 1 : 1
