Turner Syndrome and Cardiovascular Anomalies

Question 1: A 3-month-old female infant is admitted to the pediatric intensive care unit due to sudden-onset irritability, pallor, and poor feeding. She was born at term with significant lymphedema of the hands and feet. On physical examination, the infant has a webbed neck and widely spaced nipples. Cardiac auscultation reveals a systolic ejection click and a harsh systolic murmur heard best at the left infraclavicular area. Blood pressure is 110/70 mmHg in the right arm and 65/40 mmHg in the right leg. An emergent echocardiogram demonstrates a bicuspid aortic valve and an intimal flap in the ascending aorta, consistent with an aortic dissection. The patient's clinical presentation is most likely associated with which of the following genetic abnormalities? A. 47,XX,+21 B. 45,X C. 47,XXY D. 47,XXX