Electron microscopy and aggregation studies in carriers and noncarriers of the Src p.E527K variant. (A) Electron microscopy of platelets from 2 carriers of the Src p.E527K variant (patients 3 and 7), a noncarrier family member (patient 10), and a healthy control. Magnification for each image is shown (8000-20 000×). Images were acquired in a JEOL transmission electron microscope. (B) Platelet-rich plasma aggregation profiles in response to the indicated agonists from patients 3, 6, 7, and a control subject. CRP, collagen-related peptide; TRAP, thrombin receptor activating peptide (PAR-1).