Human Heredity 11th Edition by Michael Cummings

Exercise 7

Two hypothetical human conditions have been found to have a genetic basis. Suppose that a hypothetical genetic disorder responsible for condition 1 is similar to Marfan syndrome. The defect responsible for condition 2 resembles Edwards syndrome. One of the two conditions results in more severe defects, and death occurs in infancy. The other condition produces a mild phenotypic abnormality and is not lethal. Which condition is most likely lethal, and why?