Gene Interraction

Question 1

• Lethality

Answer 1

• when two copies of alleles are inherited

Question 2

Penetrance vs expressibility

Answer 2

-1.) penetrance: % of individual with mutation that show the phenotype
- incomplete or variable penetration: some individual with mutant genotype will not show mutant phenotype.eg osteogenesis imperfecta ( a dominant disorder of bone formation but some never develop symptoms
2.) Expressivity: differing level that phenotype is expressed.
- variables expressivity: some individual shows differing degrees of phenotype ex: polydactyly in cats- dominant traits, but affected cats have differing numbers of extra toes, may have one or two extra toes