基因突变引起特定的蛋白异常,造成不同程度的机械脆性和水疱,这是大疱性表皮松解症的特征。这是因为真皮-表皮黏附需要有正常数量、并在超微结构上合理分布的真皮、表皮和基底膜蛋白和蛋白多糖。
遗传性大疱性表皮松解症遗传方式包括:常染色体显性遗传和常染色体隐性遗传。[1]Fine J-D, Burge SM. Genetic blistering diseases. In: Burns T, Breathnach S, Cox N, et al, eds. Rook's Textbook of Dermatology. 8th ed. Oxford: Wiley-Blackwell; 2010: 39.1-39.37.[6]Fine JD, Eady RA, Bauer EA, et al. Revised classification system for inherited epidermolysis bullosa: report of the Second International Consensus Meeting on diagnosis and classification of epidermolysis bullosa. J Am Acad Dermatol. 2000;42:1051-1066.http://www.ncbi.nlm.nih.gov/pubmed/10827412?tool=bestpractice.com 所有遗传性大疱性表皮松解症亚型都是由于编码表皮或皮肤基底膜区域(真皮-表皮交界)内的特定结构蛋白的基因突变造成的。[1]Fine J-D, Burge SM. Genetic blistering diseases. In: Burns T, Breathnach S, Cox N, et al, eds. Rook's Textbook of Dermatology. 8th ed. Oxford: Wiley-Blackwell; 2010: 39.1-39.37.[6]Fine JD, Eady RA, Bauer EA, et al. Revised classification system for inherited epidermolysis bullosa: report of the Second International Consensus Meeting on diagnosis and classification of epidermolysis bullosa. J Am Acad Dermatol. 2000;42:1051-1066.http://www.ncbi.nlm.nih.gov/pubmed/10827412?tool=bestpractice.com 三种罕见的基底上层单纯型大疱性表皮松解症亚型是由于编码桥粒斑菲素蛋白 1、斑珠蛋白或桥粒斑蛋白的基因突变引起的。[2]Fine JD, Bruckner-Tuderman L, Eady RA, et al. Inherited epidermolysis bullosa: updated recommendations on diagnosis and classification. J Am Acad Dermatol. 2014;70:1103-1126.http://www.jaad.org/article/S0190-9622(14)01040-8/fulltexthttp://www.ncbi.nlm.nih.gov/pubmed/24690439?tool=bestpractice.com[7]McGrath JA, McMillan JR, Shemano CS, et al. Mutations in the plakophilin 1 gene result in ectodermal dysplasia/skin fragility syndrome. Nat Genet. 1997;17:240-244.http://www.ncbi.nlm.nih.gov/pubmed/9326952?tool=bestpractice.com[8]Jonkman MF, Pasmooij AM, Pasmans SG, et al. Loss of desmoplakin tail causes lethal acantholytic epidermolysis bullosa. Am J Hum Genet. 2005;77:653-660.http://www.sciencedirect.com/science/article/pii/S0002929707610131http://www.ncbi.nlm.nih.gov/pubmed/16175511?tool=bestpractice.com 基底膜上层单纯型大疱性表皮松解症的一种变体——肢端脱皮综合征——与角膜下皮肤纹理有关,是由编码谷氨酰胺转移酶 -5 的基因突变造成的。在弗莱堡(德国城市)进行的研究中,大部分单纯型大疱性表皮松解症患者(这些患者无法从分子角度进行特征描述)患有肢端脱皮综合征。[9]Kiritsi D, Cosgarea I, Franzke CW, et al. Acral peeling skin syndrome with TGM5 gene mutations may resemble epidermolysis bullosa simplex in young individuals. J Invest Dermatol. 2010;130:1741-1746.http://www.ncbi.nlm.nih.gov/pubmed/20164844?tool=bestpractice.comA mutation in the cystatin A gene has also been reported as a target for mutation in APSS. 报告显示,造成肢端脱皮综合征的基因突变也会引起胱抑素 A 基因突变。[10]Krunic AL, Stone KL, Simpson MA, et al. Acral peeling skin syndrome resulting from a homozygous nonsense mutation in the CSTA gene encoding cystatin A.http://www.ncbi.nlm.nih.gov/pubmed/23534700?tool=bestpractice.com而另一种基底膜上层亚型——表浅型单纯型大疱性表皮松解症——的分子基础目前还不清楚。[2]Fine JD, Bruckner-Tuderman L, Eady RA, et al. Inherited epidermolysis bullosa: updated recommendations on diagnosis and classification. J Am Acad Dermatol. 2014;70:1103-1126.http://www.jaad.org/article/S0190-9622(14)01040-8/fulltexthttp://www.ncbi.nlm.nih.gov/pubmed/24690439?tool=bestpractice.com[11]Fine JD, Johnson L, Wright T. Epidermolysis bullosa simplex superficialis: a new variant of epidermolysis bullosa characterized by subcorneal skin cleavage mimicking peeling skin syndrome. Arch Dermatol. 1989;125:633-638.http://www.ncbi.nlm.nih.gov/pubmed/2653224?tool=bestpractice.com
大多数单纯型大疱性表皮松解症基底膜亚型是由于角蛋白基因(K5 和 K14)突变造成的。[1]Fine J-D, Burge SM. Genetic blistering diseases. In: Burns T, Breathnach S, Cox N, et al, eds. Rook's Textbook of Dermatology. 8th ed. Oxford: Wiley-Blackwell; 2010: 39.1-39.37.[6]Fine JD, Eady RA, Bauer EA, et al. Revised classification system for inherited epidermolysis bullosa: report of the Second International Consensus Meeting on diagnosis and classification of epidermolysis bullosa. J Am Acad Dermatol. 2000;42:1051-1066.http://www.ncbi.nlm.nih.gov/pubmed/10827412?tool=bestpractice.com[12]Fuchs EV. The molecular biology of epidermolysis bullosa simplex. In: Fine JD, Bauer EA, McGuire J, et al, eds. Epidermolysis bullosa: clinical, epidemiologic, and laboratory advances, and the findings of the National Epidermolysis Bullosa Registry. Baltimore, MD: Johns Hopkins University Press; 1999:280-299. 也出现了一些罕见病例,这些病例是由于编码 EXPH5(Slac2-b)和大疱性类天疱疮抗原 1(BP230;BPAG-1)的基因突变引起的。[13]Groves RW, Liu L, Dopping-Hepenstal P, et al. A homozygous nonsense mutation within the dystonin gene coding for the coiled-coil domain of the epithelial isoform of BPAG1 underlies a new subtype of autosomal recessive epidermolysis bullosa simplex. J Invest Dermatol. 2010;130:1551-1557.http://www.jidonline.org/article/S0022-202X(15)34855-7/fulltexthttp://www.ncbi.nlm.nih.gov/pubmed/20164846?tool=bestpractice.com
伴斑状色素沉着的单纯型大疱性表皮松解症是由于 K5 突变造成的,而网格蛋白基因(半桥粒的一种成分)突变会造成单纯型大疱性表皮松解症 Ogna 型,伴肌营养不良的单纯型大疱性表皮松解症,罕见情况下也会造成伴幽门闭锁的单纯型大疱性表皮松解症。[14]Uttam J, Hutton E, Coulombe PA, et al. The genetic basis of epidermolysis bullosa simplex with mottled pigmentation. Proc Natl Acad Sci USA. 1996;93:9079-9084.http://www.pnas.org/content/93/17/9079.full.pdfhttp://www.ncbi.nlm.nih.gov/pubmed/8799157?tool=bestpractice.com[15]Uitto J, Pulkkinen L, Smith FJ, et al. Plectin and human genetic disorders of the skin and muscle. Exp Dermatol. 1996;5:237-246.http://www.ncbi.nlm.nih.gov/pubmed/8981021?tool=bestpractice.com[16]Koss-Harnes D, Høyheim B, Anton-Lamprecht I, et al. A site-specific plectin mutation causes dominant epidermolysis bullosa simplex Ogna: two identical de novo mutations. J Invest Dermatol. 2002;118:87-93.http://www.ncbi.nlm.nih.gov/pubmed/11851880?tool=bestpractice.com[17]McLean WH, Pulkkinen L, Smith FJ, et al. Loss of plectin causes epidermolysis bullosa with muscular dystrophy: cDNA cloning and genomic organization. Genes Dev. 1996;10:1724-1735.http://genesdev.cshlp.org/content/10/14/1724.full.pdf+htmlhttp://www.ncbi.nlm.nih.gov/pubmed/8698233?tool=bestpractice.com
伴幽门闭锁的单纯型大疱性表皮松解症主要是由于编码两条整合素 α6β4 链的基因突变引起的,尽管网格蛋白突变也可能造成同一表型单纯型大疱性表皮松解症。[18]Vidal F, Aberdam D, Miquel C, et al. Integrin b4 mutations associated with junctional epidermolysis bullosa with pyloric atresia. Nat Genet. 1995;10:229-234.http://www.ncbi.nlm.nih.gov/pubmed/7545057?tool=bestpractice.com[19]Shimizu H, Suzumori K, Hatta N, et al. Absence of detectable alpha 6 integrin in pyloric atresia-junctional epidermolysis bullosa syndrome. Application for prenatal diagnosis in a family at risk for recurrence. Arch Dermatol. 1996;132:919-925.http://www.ncbi.nlm.nih.gov/pubmed/8712842?tool=bestpractice.com[20]Pfendner E, Uitto J. Plectin gene mutations can cause epidermolysis bullosa with pyloric atresia. J Invest Dermatol. 2005;124:111-115.http://www.ncbi.nlm.nih.gov/pubmed/15654962?tool=bestpractice.com
任何编码 3 条层粘连蛋白 -332 链的基因突变是造成重度全身交界型大疱性表皮松解症及大部分全身中度严重型交界型大疱性表皮松解症的原因。这种突变影响透明层的结构完整性,也可能影响锚丝。[21]Varki R, Sadowski S, Pfendner E, et al. Epidermolysis bullosa. I. Molecular genetics of the junctional and hemidesmosomal variants. J Med Genet. 2006;43:641-652.http://www.ncbi.nlm.nih.gov/pubmed/16473856?tool=bestpractice.com
XVII 型胶原蛋白(大疱性类天疱疮抗原-2;BP180)基因突变是造成许多全身性中度严重型交界型大疱性表皮松解症,尤其是全身性良性交界型大疱性表皮松解症的病因。[21]Varki R, Sadowski S, Pfendner E, et al. Epidermolysis bullosa. I. Molecular genetics of the junctional and hemidesmosomal variants. J Med Genet. 2006;43:641-652.http://www.ncbi.nlm.nih.gov/pubmed/16473856?tool=bestpractice.com
整合素 α3 亚单元基因突变可见于累及肾脏和呼吸道的交界型大疱性表皮松解症患者。
所有类型的显性遗传营养不良型大疱性表皮松解症和隐性营养不良型大疱性表皮松解症是由于 VII 型胶原蛋白基因突变造成的。[22]Varki R, Sadowski S, Uitto J, et al. Epidermolysis bullosa. II. Type VII collagen mutations and phenotype/genotype correlations in the dystrophic subtypes. J Med Genet. 2007;44:181-192.http://www.ncbi.nlm.nih.gov/pubmed/16971478?tool=bestpractice.com这种蛋白是锚丝的一种主要成分,帮助致密层附着于真皮最上层。Kindler 综合征是由于 kindlin-1 基因 (FFH1) 突变引起的。[23]Siegel DH, Ashton GH, Penagos HG, et al. Loss of kindlin-1, a human homolog of the Caenorhabditis elegans actin-extracellular-matrix linker protein UNC-112, causes Kindler syndrome. Am J Hum Genet. 2003;73:174-187.http://www.sciencedirect.com/science/article/pii/S0002929707639032http://www.ncbi.nlm.nih.gov/pubmed/12789646?tool=bestpractice.com