Chapter 22, Problem 18RQ

What is the genetic basis and phenotype for each of the following disorders (use proper genetic notation)? a. Edwards syndrome b. Patau syndrome c. Klinefelter syndrome d. Down syndrome

A couple has had a child born with neurofibromatosis. They come to your genetic counseling office for help. After taking an extensive family history, you determine that there is no history of this disease on either side of the family. The couple wants to have another child and wants to be advised about the risks of that child having neurofibromatosis. What advice do you give them?