Red-green color blindness means that a person cannot distinguish shades of red and green (usually blue- green), but their ability to see is normal. There are no serious complications; however, those affected may not be considered for certain occupations involving transportation or the Armed Forces where color recognition is required. O Your role: Genetic Counselor O Scenario: James and Sophia having Breakfast conversation 4 Sex-Linked Traits: 1. Normal Color Vision: A: 29, B: 45, C: --, D: 26 2. Red-Green Color-Blind: A: 70, B:, C: 5, D: -- 3. Red Color-blind: A: 70, B:, C: 5, D: 6 James: Are you sure you want to wear that new shirt to work today? A green and red shirt like that would be better for Christmas, not for St. Patrick's Day. Sophia: Oh no! Not again! I hate being color blind! I really thought this shirt was just different shades of green. Where's the red? O Scenario: At Dinner That Night 4. Green Color-Blind: A: 70, B:, C: 5, D: 2 Sophia: We should try to find a way to make sure we only have sons, no daughters. I don't want to have any daughters who might be color blind and have so many problems like I do. Color blindness wouldn't matter so much for a boy. James:: Remember, the doctor said that, since I'm not color blind, none of our daughters would be color blind, only our sons. Sophia That doesn't make any sense. Our daughters should be color blind like me and our sons should be normal like you. James:: No, the doctor said the gene for color blindness is on the X chromosome, so only our sons will inherit your colorblindness. Sophia: I don't agree. Girls have more X chromosomes than boys, so girls should be more likely to be color blind. Help James explaining to Sophia why the doctor was right by answering the following questions. Since the allele for color blindness is recessive and located on the X chromosome, use the symbol Xcb for an X chromosome with the allele for color blindness and XCB for an X chromosome with the normal allele. 1. Write the possible genotype of Jamie: 2. Write the possible genotype of Sophia:_ 3. Draw the Punnett square for this couple and their children. Write the gametic composition of parents, circle each female offspring. Use arrows to indicate any colorblind offspring. 4. Write an explanation to help Sophia understand why their daughters will not be colorblind like their mother.