Southern Analysis of the 230-kD Bullous Pemphigoid Antigen Gene in Normal Humans, Animals, and Patients with Junctional Epidermolysis Bullosa

• Published in: Journal of investigative dermatology Vol. 97; no. 2; pp. 249 - 253
• Main Authors: Amagai, Masayuki, Elgart, George W, Klaus-kovtun, Vera, Stanley, John R
• Format: Journal Article
• Language: English
• Published: Danvers, MA Elsevier Inc 01.08.1991; Nature Publishing
• Subjects: Amphibia; Animals; Anura; Autoantigens - genetics; Biological and medical sciences; Blotting, Southern; Bullous diseases of the skin; Carrier Proteins; Cattle; Chickens; Collagen; Collagen Type XVII; Cytoskeletal Proteins; Dermatology; DNA - genetics; Dogs; Dystonin; Epidermolysis Bullosa, Junctional - genetics; Epidermolysis Bullosa, Junctional - immunology; Haplorhini; Humans; Medical sciences; Mice; Nerve Tissue Proteins; Non-Fibrillar Collagens; Pemphigoid, Bullous - immunology; Phylogeny; Rabbits; Saccharomyces cerevisiae; Species Specificity; Antigen; Bullous dermatosis; Human; Junctional epidermolysis bullosa; Skin disease; Gene
• ISSN: 0022-202X; 1523-1747
• DOI: 10.1111/1523-1747.ep12480358

To begin to characterize the 230-kD bullous pemphigoid antigen (BPA) gene, we performed Southern analysis on genomic DNA with probes derived from 7kb of cDNA that spans most of the coding region of this hemidesmosomal plaque protein. When hybridized to a 1-kb fragment of this BPA cDNA, normal human genomic DNA digested with EcoRI, BamHI, PstI, HindIII, or EcoRV showed only a single band, which was unique for each enzyme, indicating a single human gene for BPA. To determine if a related gene exists in animals, we used probes covering the full 7kb of cDNA for Southern analysis of genomic DNA from various vertebrates. A related gene was detected in other mammals (monkey, cow, dog, rabbit, mouse, and rat) but not in chicken, frog, or fish. Under these same hybridization conditions a probe for human β-actin could detect an actin gene in all these species. Furthermore, immunofluorescence showed that an antibody raised against portions of the 230-kD BPA bound to the epidermal basement membrane of mammals but not that of a bird or amphibian. Finally, because most patients with junctional epidermolysis bullosa (JEB) have defective hemidesmosomes in ultrastructure, and probably function, we analyzed genomic DNA from these patients. No restriction fragment length polymorphisms (RFLP) were detected when the DNA from 11 normals and 8 JEB patients (representing 16 possible defective genes) was digested with BamHI, EcoRI, or PstI and hybridized to any part of the cDNA. These findings indicate that 1) there is a single BPA gene in humans; 2) a closely related gene exists in other mammals but not birds, amphibia, or fish; and 3) gross abnormalities of the BPA gene are not characteristic of JEB patients.