Genetic analysis and diagnosis of skeletal dysplasias

为了建立骨骼发育不良、骨和软骨遗传性疾病的DNA诊断体系，并深入了解其发病机制，我对骨骼发育不良进行了遗传分析，获得了以下结果。Shwachman综合征候选基因的分离分析了与Shwachman综合征相关的新的相互易位(t(6；12)(q16.2；q21.2))。我克隆了易位断裂点并确定了DNA序列。我发现了一个被断点干扰的基因，这是Shwachman综合征的候选基因。新的候选基因的分离通过电子克隆，我克隆了骨骼发育不良的新候选基因，ASH2(类ash2)，PROSC(共转录的)，C8orf2，CILP(软骨中间层蛋白)，PRG4(蛋白多糖4)。测定了这些基因的基因组结构和染色体定位，并对其表达进行了分析。Engelamnn病候选基因的确定通过与Niikawa教授的研究小组合作，通过定位候选基因的方法，我发现了Engelmann病的致病基因是转化生长因子β1.4。X连锁显性点状软骨发育不良EBP基因突变分析发现，X连锁显性点状软骨发育不良有5个新的EBP基因突变，其中3个为无义突变，2个为错义突变。我发现患者的EBP酶活性与其基因分型有很好的相关性。

To establish a system for DNA diagnosis of skeletal dysplasias, genetic disorders of bone and cartilage, and gain insight for their pathogenesis, I performed genetic analysis of skeletal dysplasias and obtained the following results.1. Isolation of a candidate gene for Shwachman syndromeI analyzed a de novo reciprocal translocation, (t(6 ; 12)(q16.2 ; q21.2)) associated with Shwachman syndrome. I cloned the translocation breakpoints and determined the DNA sequences. I identified a gene that is disrupted by the breakpoint, a candidate gene for Shwachman syndrome.2. Isolation of novel candidate genesThrough in silico cloning, I cloned novel candidate genes for skeletal dysplasias, ASH2L (ash2-like), PROSC (proline synthetase co-transcribed), C8orf2, CILP (cartilage intermediate layer protein), PRG4 (proteoglycan 4). I determined genomic structure and chromosomal localization of the genes, and analyzed their expression.3. Identification of a candidate gene for Engelamnn diseaseIn collaboration with Prof.Niikawa's group by a positional candidate gene approach, I found the disease gene for Engelmann disease is TGF-beta1.4. Mutation analysis of EBP gene in X-linked dominant chondrodysplasia punctataI identified 5 novel mutations of the EBP (emopamil-binding protein) gene in X-linked dominant chondrodysplasia punctata ; three of them were nonsense and two missense mutations. I found the enzyme activity of EBP in the patients correlated well with the genotype.