She ordered the test. Eli's mother wept on the phone three weeks later: positive.

Marcus re-ran her numbers. He had missed the soft palate, the high-arched roof of her mouth that she'd mentioned offhand ("My dentist always complains about my palate"). He had missed the skin striae, dismissing them as stretch marks from pregnancy. The calculator had weighted those at 2.1 and 1.8 respectively. He had input them as zeros.

This score helps doctors differentiate between Marfan syndrome and other connective tissue disorders (such as Loeys-Dietz syndrome or Ehlers-Danlos syndrome), which can share similar physical traits.