<prompt> In congenital dystrophic variety of epidermolysis bullosa, mutation is seen in the gene coiling for :Laminin 4Collagen type 7Alpha 6 integerinKeratin 14  <response>: Ans. b. Collagen type 7 Ref: Fitzpatrick k 7e p494-499; Rooks 8e p40.51-40. 56, 13. 19. 10, 12-10.28; Roxburgh 17e p90-91In a congenital dystrophic variety of epidermolysis bullosa, mutation is seen in the gene coding for collagen type 7.DisorderDirect Immunofluorescence Pattern DepositsTarget antigenPemphigus vulgaris Intercellular, intraepidermal IgG, fish netesmogiein 3Pemphigus foliaceus Intercellular, intraepidermal IgG, fish netDesmoglein 1Paraneoplastic pemphigusIntercellular and subepidermal IgG, fish netPlakins desmoplakin, envoplakin, periplakin, BP 230Bullous pemphigoidBasement membrane zone IgG, linearBP23G BP180Herpes gestationalBasement membrane zone IgG, linearBP23G BP180Dermatitis herpetiformis Dermal papillae IgA, granular Epidermal tissue trnasglutami naseLinear IgA diseaseBasement membrane zone IgA, linearBP180Epidermolysis bullosa dystrophicaBasement membrane zone IgG, linearCollagen VIIanchoring fibrilEpidermolysis BullosaEpidermolysis bullosa congenita is inherited genodermatoses genetic disorderEpidermolysis bullosa acquisita is a sporadic autoimmune bullous diseaseCharacterized by the skin and related epithelial tissue break and blisters as a result of minor trauma.Pathology: Alpha chain of collagen 7 is defective in EB acquisita and EB dystrophicClinical Features:Skin fragility, spontaneous or trauma-induced non-inflammatory tense bulla over trauma-prone surfaces such as sacral area, elbow, knee, back of hands.Lesions heal with scarring, scaling, crust formation or erosions and pearl-like milia cyst formationDiagnosis:Direct immune electron microscopy gold standard and direct immunofluorescence DIF of perilesional skin show intense, linear, homogenous fluorescent band of IgG and C3 at the dermoepidermal junction. 