Genetics Problems

Step 1: Write down the information you have. What is the dominate allele, and what is the recessive allele? Who exhibits dominant traits? Is their genotype heterozygous (different alleles) or homozygous (having all the same alleles)? etc
ex. A is dominant, a is recessive
Step 2: write down the genotypes of the parents, mother first
Step 3: write down the gametes- separate each allele
Step 4: draw a Punnet Square and multiply each gamete against the other gametes.
ex. AA x Aa = AA, AA, AA, Aa
Step 5: rewrite your results as ratios
P : 4 dominant, 0 recessive
G: 3 AA: 1Aa: 0aa

the types of ratios possible

AA x AA
P:4dom:0 rec
G:4AA:0:0

AAxAa
P : 4 dominant, 0 recessive
G: 3 AA: 1Aa: 0aa

AA x aa
P: 4 dom, 0 rec
G:0:4Aa:0

Aa x Aa
AA Aa Aa aa
P: 3 dom :1 rec
G: 1 AA: 2 Aa: 1 aa

aa x Aa
Aa Aa aa aa
P: 2 dom: 2 rec
G: 0:2Aa:2aa

aa x aa
P: 0 dom: 4 rec
G: 0:0:4aa