Mutation Of Keratin1in Epidermolytic Hyperkeratosis

Ichthyosis is a group of partners with dry skin, placoid scale wich iscaused by stability mechanism and keratinnization disorder of epidermiccells.According to the variety of genetic mechanism,clinicalmanifestation and histopathology, ichthyosis is mainly divided intofour types: Ichthyosis Vulgaris(IV), Epidermolytic Hyperkeratosis(EHK),X-linked Ichthyosis(XLI) and Nonbullous Congenital IchthyosiformErythroderma(NCIE).EHK,wich is also called bullous ichthyosiform erythroderma(BCIE),is aautosomal dominant inherited disease caused by mutations inkeratin1(KRT1) and keratin10(KRT10) gene. As the result of themutation, Keratinocyte membrane is assembled incorrectly, which leadsto the keratinization disorder of epidermis.This study detected all theexons of KRT1and KRT10gene,in order to find new mutations andenrich the gene mutations spectrum.Materials and Methods：1Materials：1.1Object of the study: An epidermolytic hyperkeratosis family ofJilin province diagnosed by department of dermatology of the secondhospital of Jilin university. Mother and son are patients who havesimilar clinical manifestations. 1.2Major reagents:EDTA,10%SDS,boric acid, proteinase K,chloroform,Tris saturated phenol,alcohol,chloroform, ethidiumbromide,TBE buffer,2×Taq plus PCR MIX.2Methods： Biopsy punch were taken from typical lesions forhistopathological examination by light microscopy. Blood samples weretaken from all the family members and50normal human controls andgenomic DNA was extracted. Exons gene of KRT1and KRT10weredetected by polymerase chain reaction(PCR) and DNA sequencing.Rsults：There was a single heterozygous point mutation in KRT1gene,i.e.1432G→C of KRT1,leading to an amino acid alteration ofglutamate to glutamine.Conclusion：KRT1E478Q mutations were the cause of the phenotype inthis two cases, which was reported only once previously inGermany.this result further enriched the gene mutation spectrum ofChinese people.