A 33-year-old woman, gravida 2 para 1, comes to the office for a prenatal visit at 20 weeks gestation. She feels well and reports experiencing fetal movements. The patient has no medical problems other than a history of cleft lip, which was repaired in childhood. Her husband is healthy, but her previous child was born with spina bifida. She takes a daily prenatal vitamin. Physical examination is unremarkable and uterine size is in accordance with ultrasound dates. The patient is worried that the fetus may develop the same birth defect as her previous child. Which of the following is the most likely mode of inheritance of this disorder?

Question

A 33-year-old woman, gravida 2 para 1, comes to the office for a prenatal visit at 20 weeks gestation.  She feels well and reports experiencing fetal movements.  The patient has no medical problems other than a history of cleft lip, which was repaired in childhood.  Her husband is healthy, but her previous child was born with spina bifida.  She takes a daily prenatal vitamin.  Physical examination is unremarkable and uterine size is in accordance with ultrasound dates.  The patient is worried that the fetus may develop the same birth defect as her previous child.  Which of the following is the most likely mode of inheritance of this disorder?

Quizplus · Accepted Answer

Eductional Objective: Many frequently encountered diseases (eg, hypertension, spinal bifida) display multifactorial inheritance, which involves the complex interaction of numerous genetic and environmental factors to determine phenotypic expression.  Although the exact inheritance risk cannot be determined, the closer a relative is to the affected person, the more likely the relative is to develop the trait.

A 33-Year-Old Woman, Gravida 2 Para 1, Comes to the Office