Genetics Recognition

Question 1

• What are common physical exam features that should clue you in to the possibility of Treacher Collins Syndrome(TCS)?
• What pathologies does TCS predispose patients to?
• Are pts with TCS intellectually disabled?

Answer 1

• malar and zygomatic hypoplasia with downslanting palpebral fissures; prominent nose; Pierre-Robin sequence; small, posteriorly rotated, and malformed ears; and lower eyelid colobomas with absent eyelashes. Look at the parents, it is autosomal dominant so odds are one of them will have it
• Pathologies-speech airway and feeding difficulties from Pierre-Robin sequence, vision loss/strabismus, conductive hearing loss, rarely renal or cardiac malformations.
• They have normal intelligence

Question 2

• What is lesch-Nyhan syndrome?
• How does it present and what lab abnormality is most common?
• What is the most common behavioral disturbance of these patients?

Answer 2

• Lesch-Nyhan syndrome is a uric acid metabolism disorder
• Presents with motor dysfunction resembling cerebral palsy, behavioral disturbances, cognitive impairment, self-injurious behaviors, and hyperuricemia.
• Self-injurious behavior is a consistent clinical manifestation of Lesch-Nyhan disorder.