Clinical findings in the 4 affected males included a tall slender habitus (3) (the fourth was tall but muscular), a long-narrow face (3), large head (4), highly arched palate (4), small mandible (4), abnormal speech (4), hypernasal voice (3), joint hyperextensibility (3), borderline to large testes (3), pectus excavatum (2), atrial septal defect (1), and a double row of teeth (1).