Objective To identify a locus at chromosome coding for hereditary palmoplantar keratoderma of three Chinese pedigrees.Methods The genome scan was conducted with microsatellite markers on chromosome 12(D12S85、D12S368、D12S83、D12S345)and 17(D17S1868、D17S787、D17S1857、D17S798、D17S944、D17S949)respectively on the ABI 3100 Genetic Analyzer(Applied Biosystems).Two-point LOD score was calculated.Results The maximum two-point LOD score 6.59 and 5.96 at ?=0.1 were obtained at D17S1868 and D17S787 on chromosome 17q12～q21.It is an evidence of linkage between this disease and KRT9 which has been mapped within the region.Conclusion There is a locus responsible for this disease on chromosome 17q12～q21.

Objective To evaluate the prevalence of the DJ-1 mutation in early-onset Parkinson's disease (EOPD) patients,and analyzed the association between the certain polymorphic marker g.168_185del in intron1 and Parkinson' s disease (PD).Methods We screened all 7 exons and exon-intron boundary regions of DJ-1 by PCR and direct nucleotide sequencing in 90 Chinese patients with EOPD.We also compared the allele and genotype frequencies of the g.168_185del polymorphism between EOPD patients and controls.Results We found no causative DJ-1 mutations in our cohort of Chinese EOPD patients.But we did identified 4 known polymorphic variants,including the g.168_185del in intron 1,g.5027G ＞ A (rs17523802),g.5065T ＞ C (rs226249),and g.5094C ＞ T (rs11121064) within exon 1.Del/Ins frequencies of the g.168_185 del polymorphism were 11.1％ (10/90)and 13.3％ (14/105) in EOPD group and normal group,respectively.Ins/Ins frequencies were 88.9％ (80/90) and 86.7％ (91/105),thex2 and P value of genotype frequency were 0.222 and 0.669 between EOPD patients and controls,respectively.The insert frequencies were 94.4％ (170/180)and 93.3％ (196/210) in EOPD patients and controls,the deletion frequencies were 5.6％ (10/180) and 6.7％ (14/210),thex2 and P value of allele frequency were 0.207 and 0.679 between EOPD patients and normal,respectively.Furthermore,the P value of genotype and allele frequencies were 0.736 and 0.744 between familial EOPD patients and controls,respectively;P values of genotype and allele frequencies were 0.847 and 0.852 between sporadic EOPD patients and control group,respectively.There was no statistical difference between groups.Conclusion Mutations in DJ-1 are uncommon in Chinese EOPD patients,and no association is observed between the DJ-1 intron 1 g.168_185del polymorphism and risk of PD.

Objective To construct the eukaryotic expression vector encoding IT15 gene and detect its expression in SH-SY5Y cells.Methods The exon1 of IT15 gene was amplified from genomic DNA isolated from a healthy adult and a Huntington disease patient lymphoblastoid cell lines by PCR.PCR products were subcloned into eukaryotic expression vector pEGFP-C1.The SH-SY5Y cells were transiently transfected with the recombinant plasmids and observed under fluorescence microscope.Western blot was used to detect the expression of the fusion protein.Results PCR products had approximately 170 and 310 bp specific segments.The recombinant eukaryotie expression plasmids were confirmed by restriction endonuclease analysis and sequencing.The N-terminal fragment of normal huntingtin primarily localized in the cytoplasim of SH-SY5Y cells,while the N-terminal fragment of mutant huntingtin aggregated both perinuclearly and intranuelearly.Conclusions The recombinant eukaryotic expression vectors encoding wild type and mutant IT15 gene fragments are useful for studying pathogenesis of Huntington disease.The Nterminal fragment of mutant huntingtin aggregats both perinuclearly and intranuclearly,which could be important for Huntington disease pathophysiology.