A newborn female is evaluated for poor feeding, a weak cry, and hypotonia. Physical examination reveals a cleft palate, hypertelorism (wide-set eyes), a broad nasal bridge, and micrognathia (small jaw). A harsh systolic murmur is heard along the left upper sternal border. Laboratory testing shows severe hypocalcemia. An echocardiogram confirms truncus arteriosus. Which of the following statements is correct regarding the most likely etiology of this patient’s condition?
