Family Pedigrees

• What is cystic fibrosis (CF) classified as?

  A genetic condition
• What type of allele causes cystic fibrosis?

  A recessive allele
• How can pedigree analysis be used in genetics?

  To study inheritance of dominant and recessive alleles
• How can a family pedigree be utilized?

  • Show inheritance of a genetic condition
  • Predict chances of inheriting faulty alleles
• What does a family pedigree illustrate regarding cystic fibrosis?

  Inheritance of the condition within a family
• How do you calculate the probability of a child having cystic fibrosis using a pedigree?

  By using a Punnett square
• What is the probability of Gil and Harry having a child with cystic fibrosis if one parent has it?

  25%
• What are the steps to calculate probabilities using a Punnett square?

  1. Determine parental genotypes
  2. Set up the Punnett square
  3. Fill in the square with possible allele combinations
  4. Count the outcomes for each genotype
  5. Calculate probabilities based on total outcomes