Use the following pedigree shown below for a family in which dark-shaded symbols represent individuals with one of the two major types of colon cancer. Numbers under the symbols are the individual's age at the time of diagnosis.

-The affected woman in generation IV is thinking about her future and asks her oncologist (cancer specialist)whether she can know whether any or all of her children will have a high risk of the same cancer. The doctor would be expected to advise which of the following? I. genetic counselling
II. prenatal diagnosis when/if she becomes pregnant
III. testing to see whether she has the allele
IV. testing to see whether her future spouse or partner has the allele

Question

Use the following pedigree shown below for a family in which dark-shaded symbols represent individuals with one of the two major types of colon cancer. Numbers under the symbols are the individual's age at the time of diagnosis.
 
-The affected woman in generation IV is thinking about her future and asks her oncologist (cancer specialist)whether she can know whether any or all of her children will have a high risk of the same cancer. The doctor would be expected to advise which of the following? I. genetic counselling
II. prenatal diagnosis when/if she becomes pregnant
III. testing to see whether she has the allele
IV. testing to see whether her future spouse or partner has the allele

Quizplus · Accepted Answer

The affected woman's family has a history of colon cancer, suggesting that there may be a genetic basis for the disease. Therefore, the oncologist should advise genetic counselling to determine the risk of colon cancer for her children. Prenatal diagnosis would be an option for any future pregnancies, allowing parents to make informed decisions about the child's health. However, testing to see whether she or her future partner has the allele would not be helpful because the inheritance pattern of colon cancer is complex and involves multiple genes. Therefore, knowing the status of one gene would not give reliable information about the overall risk of developing colon cancer.

Use the Following Pedigree Shown Below for a Family in Which