Mapping And Cloning Of Dentinogenesis Imperfecta Type Ⅱ

Dentinogenesis imperfecta (DGI) is an autosomal dominant disorder of dental development that occurs with an incidence of approximately 1:8000 live births. It was classified into three subgroup: Type I ,Type II (DGI- II) and Type 1ll(DGI-III). DOT Type I is associsted with osteogenesis imperfecta. DGI- II is the classically inherited disease affecting dentin formation only. DGI-m is found in a southern Maryland tn-racial inbred population known as the 揃randywine isolation? As the molecular basis of DGI Type I has been elucidated which is caused by heterogeneous mutations of the Type I collagen gene and DGJ-JII is restricted in a certain region, now most researches are focus on the DGI- 11. 1 Mapping of Dentinogenesis Imperfecta Type II With the development of the DNA markers, the critical region of DGI- II had become more and more refined. Recently, Aplin HM mapped the DOT-IT to an interval of less than 2cM between GATA62ATT and D4S 1563 at human chromosome 4q21. In the current investigation, two Chinese DOT-TI pedigrees were collected. Linkage analysis with nine short tandem-repeat polymorphisms(STRPs) had showed that the DOT-TI locus was located between markers D4S 1534 and D4S2623, which was similar to the report of Aplin HM抯. ———————————————一SWN医X学谆士掌位论文＿＿＿一．＿．＿．．＿＿ 2 ConswMu ofbuman t000gcrm MAMrary CWg c「A h［W is a class］wwgyto」Wfy new genes．For Dl11 mmdy呷sc地 asthedi帅ance ofde恤fo皿劝on咖mn响i咖on, and the developttient oftooth begins rom。byo,constrUCting a hUman tooth germ cDNA librny will be helpful to soparate g。es that ptclpate m tooth development二 Pnmny to4germs,seleete4to consirtlCt a…11bry using＞art… LibW COnstruchon KH．he ie of the libr聊 was 0．SX 106 pm／llil and he percenteqe ofrecoMmant Mnes was 83％．…on Of一 toM germ cDNA ltw ill aid n filr［ller SCYCC］:］Illg COdCll SCqllCllCCS ill hC CliCal fCgloll． 3 恤tation scmenmgofDGLll candldategen辟 Wi he pTOgress of hman ghome research,more nd more genes had been located to a region of咖mosome,so candidate gM moe cutied region can be searched direCtly from GDB帅:ywww；gdb．ofg)．On chromosome 4qZI,there m而Me mop genes encoeq d盼讪 W bone既饲celldar m咖 prems ncluding BSP, SPPI,DMPI,DSPP et al．Previous researches had excluded BSP SPP and DMP rom a causative role m he pathogenesis of DGI－11．In tis studX m血址ons wee s忧ened In all these genes ithPCLSSCP and Se叫encing,恤 we just provided he data of Dmel and DSPP．he results showed that there ws no disease－speclBc皿帅叨on In DMPI,so n ws excb的d bm a cans缸we role of伽s disease．But m DSPR SSCP咖 sempmp reveded a G,A transNon m the donor Splice sitep of mron 3 n all he姐吻劝 members of family A．S咖一 analysis s吧ge吮d that them皿叨on ws ikely to re刑t m exon－ski卯呕 ith a loss of趴on3,Wn山encodedp咖毗d咖n sialoProtem．In抽血yB,all he疵砒d members camea a G～T conversion m the first nucleotide of exon 3,wich is pre山cbd to res血 m a s汕劝N在讪 ofVlVl by We 0 codon瓜 As Ws NN咒d ws conserved n innan． rat and mouse,and it fell w1Tlllll he pTedicted ·7· Z~tfr~ transmembrane domain, this mutation may therefore interfere with the signal peptide cleavage of DSPP. As both mutations showed complete...