LIFESCI 4 Lecture Notes - Lecture 3: Punnett Square, Mendelian Inheritance, Intellectual Disability
Document Summary
Lifesci 4 - lecture 3 - extension to mendelian genetics. Pku is an inherited disorder that can lead to mental retardation if left untreated. Individuals filled in with black must be homozygous recessive (aa), and since the sibling of both mutated individuals are normal, the parents from both affected individuals must all be heterozygous carriers (aa) The individual circled in red is not affected by pku, which means that the genotypes must be aa or aa. There is a chance (due to punnett square) that she is a carrier aa. There is then a chance that the individual circled in red would pass the recessive allele (a) to the light blue individual. There is a 100% chance that the light blue individual will inherit one allele (a) from his/her affected parent. Jack whose brother has the disease marries jill whose aunt has the disease.
