In 2005, a human clinical trial began in Germany to test gene therapy as a treatment for the recessive X-linked disease Wiskott-Aldrich syndrome. The syndrome affects blood cells and causes recurrent infections, pneumonia, bleeding, and rashes. Patients often develop leukemia or lymphoma and die of complications due to infections. Felix, a boy with the syndrome, entered the trial in 2009. Blood cells were removed from his body and genetically engineered using a virus to express a functional copy of the gene that is defective in the syndrome. The genetically engineered cells were reintroduced into Felix’s body where they produced the protein that he was lacking. A year after the treatment his body was producing healthy, functional blood cells and most of his symptoms were resolved. Felix was cured!

Question

In 2005, a human clinical trial began in Germany to test gene therapy as a treatment for the recessive X-linked disease Wiskott-Aldrich syndrome. The syndrome affects blood cells and causes recurrent infections, pneumonia, bleeding, and rashes. Patients often develop leukemia or lymphoma and die of complications due to infections. Felix, a boy with the syndrome, entered the trial in 2009. Blood cells were removed from his body and genetically engineered using a virus to express a functional copy of the gene that is defective in the syndrome. The genetically engineered cells were reintroduced into Felix’s body where they produced the protein that he was lacking. A year after the treatment his body was producing healthy, functional blood cells and most of his symptoms were resolved. Felix was cured!

A. 100 percent of passing it to all of his children
B. 100 percent chance of passing it to his sons
C. 100 percent chance of passing it to his daughters

Answer 1