As part of your obstetrics rotation, you spent a night in the delivery room. One 42 year-old woman gave birth to a baby boy. During examination of the baby, you notice that the child has a flat face, wide-set eyes, slanted palpebral fissures, epicanthal folds,small ears, short neck and a single palmar crease across each hand. In palpation, you noticed abnormally low muscle tone and hyperflexible joints. Eye examination revealed white spots on the periphery of his irises. In the mother’s medical chart, you noticed that screening tests during pregnancy showed decreased Alpha-fetoprotein (AFP), Unconjugated estriol (UE3) and Pregnancy-associated plasma protein A (PAPP-A). Of the following, which is the most likely diagnosis in this baby?
