Useful Tips for solving Genetic Problems:
1. Read the question carefully to determine what type of genetics is
involved. Look for:
a. Monohybrid = has only one dominant and one recessive allele
b. Co-dominant = three different phenotypes where one is either
stripes, spots, dots, a combination of two colours, etc
c. Incomplete dominance = three different phenotypes with one
phenotype is a blend of the other two such as yellow and red
make orange
d. Multiple allele = there are more than two alleles co-dominant
with a recessive, varying levels of dominance. Ex. blood types,
rabbit colour, fly body colour
e. Dihybrid Crosses = two separate genes/traits being looked at
together. Make sure that each genotype has four letters!
2. Write out the letter system you are going to use for each allele.
3. Outline the genotypes of each parent based on the information given in
the question
4. Determine all the possible gametes for each parent. The number of
different gametes of each parent will be the rows and columns of your
Punnett square.
5. Construct a Punnett square and determine the possible offspring.
6. Identify the genotypes and phenotypes of the Punnett square. (Don’t do
the work if it is not asked.)
7. Include a statement or sentence that directly responds to the
question(s) being asked.