COL7A1基因编码胶原蛋白VII型α1链，是构成锚定纤维的主要成分，在皮肤基底膜区发挥关键作用，帮助表皮与真皮紧密连接。该基因属于胶原蛋白基因家族，这一家族的共性是其成员均编码含有Gly-X-Y重复序列的三螺旋结构域，形成稳定的三聚体结构，参与细胞外基质的构建和组织完整性维持。COL7A1表达产物VII型胶原通过C端NC1结构域与层粘连蛋白-332和IV型胶原相互作用，N端NC2结构域介导二聚化，最终形成反平行二聚体结构的锚定纤维。该基因突变会导致VII型胶原合成或功能异常，引发营养不良型大疱性表皮松解症（DEB），表现为皮肤脆性增加、轻微摩擦即形成水疱和瘢痕，严重者可影响食道、角膜等粘膜组织。COL7A1过表达可见于瘢痕疙瘩和硬皮病等纤维化疾病中，促进异常胶原沉积；而表达降低则导致皮肤机械稳定性下降。该基因与TGF-β信号通路相关，其表达受TGF-β1正调控。目前已发现超过800种致病突变，包括甘氨酸替换（影响三螺旋稳定性）、提前终止密码子（导致等位基因功能丧失）以及剪接位点突变等。隐性遗传的严重型DEB患者常出现VII型胶原完全缺失，而显性遗传的轻度DEB多由显性负效应突变引起。近年来研究还发现COL7A1在伤口愈合、肿瘤侵袭等过程中发挥作用，其表达异常可能影响角质形成细胞迁移。基因治疗策略如外显子跳跃和CRISPR/Cas9介导的基因编辑正在DEB治疗中进行探索。

该基因编码VII型胶原的α链。在第VII型胶原纤维，三个相同的阿尔法胶原链组成，被限制为复层扁平上皮下方的基底区。它用作外部上皮和下面的基质之间的锚定原纤维。在这种基因突变与各种形式的营养不良性表皮松解的相关联。在不存在的突变，但是，这种疾病的一种获得形式可能会导致从制成Ⅶ型胶原的自身免疫反应。 [由RefSeq的，2008年7月提供]

COL7A1 encodes the alpha-1 chain of type VII collagen, a critical structural component of anchoring fibrils that secures the dermal-epidermal junction by tethering the basement membrane to the underlying dermis. As a member of the collagen gene family, this gene produces a protein characterized by a central triple-helical domain composed of Gly-X-Y repeats, which assembles into stable trimers to maintain extracellular matrix integrity. The mature type VII collagen molecule features a C-terminal NC1 domain that binds laminin-332 and type IV collagen, while the N-terminal NC2 domain mediates dimerization to form antiparallel dimers, thereby establishing the robust anchoring fibril structure. Mutations in COL7A1 disrupt collagen synthesis or function, leading to dystrophic epidermolysis bullosa (DEB), a condition marked by increased skin fragility, blistering upon minor friction, and scarring, with severe cases potentially affecting mucosal tissues such as the esophagus and cornea. The severity of DEB correlates with the genetic mechanism; recessive severe forms often result in a complete absence of type VII collagen due to null mutations, whereas dominant mild forms are typically caused by dominant-negative mutations. Beyond its role in genetic disorders, COL7A1 expression is positively regulated by the TGF-β1 signaling pathway and is aberrantly elevated in fibrotic conditions like keloids and scleroderma, where it contributes to pathological collagen deposition, while reduced expression compromises mechanical skin stability. With over 800 pathogenic variants identified—including glycine substitutions that destabilize the triple helix, premature stop codons, and splice-site mutations—COL7A1 is also implicated in wound healing and tumor invasion, where its dysregulation may influence keratinocyte migration. Current therapeutic strategies for DEB are actively exploring gene-editing approaches, such as exon skipping and CRISPR/Cas9-mediated correction, to restore functional collagen expression.

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