Epidermolysis bullosa simplex (EBS) — the most common inherited EB subtype — is caused by mutations in which structural proteins?

• A Collagen XVII (BP180) and alpha-6/beta-4 integrin
• B Type VII collagen (anchoring fibrils)
• C Laminin-332 (laminin-5)
• D Keratins 5 and 14 (cytoskeletal proteins of basal keratinocytes) ✓

Explanation

Epidermolysis bullosa simplex (EBS) is caused by autosomal dominant (mostly) mutations in keratins K5 and K14, the intermediate filament proteins forming the cytoskeletal scaffolding of basal keratinocytes. Mutant keratins disrupt the cytoskeletal network, making basal cells fragile and prone to blistering with minimal trauma (intraepidermal split). Junctional EB (JEB) involves laminin-332 or collagen XVII/integrin mutations (at the lamina lucida level). Dystrophic EB (DEB) involves collagen VII mutations (sub-lamina densa split). These distinctions are diagnosed by EM and immunomapping.

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.