A 20-year-old male presents with multiple flesh-coloured papules over the trunk and neck. His father has the same lesions. Ophthalmology shows angioid streaks. Cardiovascular examination reveals peripheral arterial calcification. The gene mutated is:
- A ELN
- B FBN1
- C ABCC6 ✓
- D COL5A1
Correct answer: C. ABCC6
Explanation
Pseudoxanthoma elasticum (PXE) is caused by mutations in ABCC6 (MRP6 transporter). It is characterized by yellowish 'plucked chicken skin' papules (calcification and fragmentation of elastic fibers in dermis), angioid streaks in the retina (breaks in Bruch's membrane), and cardiovascular complications (peripheral artery disease, premature atherosclerosis). FBN1 mutations cause Marfan syndrome; COL5A1 causes Ehlers-Danlos; ELN causes cutis laxa.
Reference: Neena Khanna Illustrated Synopsis of Dermatology & STD, 6th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.