COL17A1 gene

The COL17A1 gene (Collagen Type XVII Alpha 1 Chain) is a protein coding gene located on chromosome 10q25.1. The COL17A1 gene encodes the alpha chain of collagen type XVII (see collagens below). Unlike most collagens, collagen XVII is a transmembrane protein,a structural component of hemidesmosomes, multiprotein complexes at the dermal-epidermal basement membrane zone. It mediates the adhesion of keratinocytes to the underlying membrane.

The 120 kDa linear IgA disease antigen (LAD-1 - see under Linear IgA Dermatosis) is an anchoring filament component involved in dermal-epidermal cohesion. LAD-1 is formed by proteolysis at the NH2-terminal, cell membrane portion of the extracellular domain of BP180 (antigen of bullous pemphigoid). Further proteolytic degradation at the COOH-terminus of LAD-1 results in an additional 97-kDa fragment (LABD97) that has long been considered an autoantigenic gene of linear IgA dermatosis.

1. Jonsson F et al (2015) Mutations in collagen, type XVII, alpha 1 (COL17A1) cause epithelial recurrent erosion dystrophy (ERED). Hum Mutat 36:463-473.
2. Vahedi F et al. (2018) Epithelial Recurrent Erosion Dystrophy Secondary to COL17A1 c.3156C>T Mutation in a Non-white Family. Cornea 37:909-911.