The Complete Genomic Sequence of the Machado-Joseph Disease Gene

马查多-约瑟夫病基因的完整基因组序列

• 批准号: 10670577
• 负责人: GOTO Jun
• 金额: $ 2.24万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10670577/
• 关键词: Machado-Joseph disease; Triplet repeat disease; Chromosome 14; Genome; DNA sequence; SNP; 14番染色

Machado-Joseph disease (MJD) is a progressive neurodegenerative disease that is characterized clinically by cerebellar ataxia and various associated symptoms. The disorder is the most common type among the hereditary spinocerebellar ataxias and is inherited with autosomal dominant manner. The causative genetic abnormality is an unstable expansion of the CAG repeat in the MJD gene that maps to chromosome 14q32.1. The genomic structure, expression and physiological function of the gene have been obscure. In this project we determined the complete genomic sequence of MJD to elucidate its genomic structure. We obtained totally 27 cDNA clones by screening four human cDNA libraries, 13 cosmid clones by screening the chromosome 14 specific library and 8 BAC clones by screening RPCI11 human BAC library. A contig of the size of approximately 300kb, including MJD, was constructed by the fiber FISH method. The complete sequence of a BAC clone, B445M7, was determined (175,330bp). The comparison of the genomic, cDNA and EST sequences indicated that the MJD gene spanned 48,240bp, was composed of 11 exons and transcribed at least 5 messengers (approximately 1.4, 1.9, 2.0, 4.8 and 7.0kb) by alternative splicing and polyadenylation. Northern blot analysis confirmed these results and showed the ubiquitous expression of the gene. We found three single nucleotide polymophism (SNP) sites in the coding region ; GT^<527>T/GTC, ^<669>ATG/GTG and TA^<1118>A/TAC.Haplotyping analysis showed that there were only two haplotypes in the Japanese population and the strong linkage disequilibrium was found between the CAG expansion and 527T-669A-987C-1118A haplotype.

马查多-约瑟夫病 (MJD) 是一种进行性神经退行性疾病，临床特征为小脑共济失调和各种相关症状。该疾病是遗传性脊髓小脑共济失调中最常见的类型，以常染色体显性方式遗传。致病性遗传异常是映射到染色体 14q32.1 的 MJD 基因中 CAG 重复序列的不稳定扩展。该基因的基因组结构、表达和生理功能一直不清楚。在这个项目中，我们确定了 MJD 的完整基因组序列，以阐明其基因组结构。通过筛选4个人cDNA文库共获得27个cDNA克隆，通过筛选14号染色体特异性文库共获得13个粘粒克隆，通过筛选RPCI11人BAC文库共获得8个BAC克隆。通过纤维 FISH 方法构建了大小约为 300kb 的重叠群，包括 MJD。确定了 BAC 克隆 B445M7 的完整序列（175,330bp）。基因组、cDNA和EST序列的比较表明，MJD基因全长48,240bp，由11个外显子组成，通过选择性剪接和聚腺苷酸化转录至少5个信使（约1.4、1.9、2.0、4.8和7.0kb）。 Northern印迹分析证实了这些结果并显示该基因的普遍表达。我们在编码区发现了三个单核苷酸多态性（SNP）位点； GT^<527>T/GTC、^<669>ATG/GTG和TA^<1118>A/TAC。单倍型分析表明，日本人群中只有两种单倍型，且CAG扩展与527T-669A-987C-1118A单倍型之间存在强连锁不平衡。

项目成果

Maciel, P., Gaspar, C., et al.: "Study of three intragenic polymorphisms in the Machado-Joseph disease gene (MJD1) in elation to genetic instability of the (CAG)n tract"European Journal of Human Genetics. 7. 147-156 (1999)

Maciel, P.、Gaspar, C. 等人：“马查多-约瑟夫病基因 (MJD1) 中三种基因内多态性与 (CAG)n 道遗传不稳定性的研究”《欧洲人类遗传学杂志》。

Ichikawa, Y., Hattori, M., et al.: "The gene structure of MJD"American Journal of Human Genetics. 65(4)(suppl.). A188 (1999)

Ichikawa, Y., Hattori, M., et al.：“MJD 的基因结构”美国人类遗传学杂志。

Hazeki N,Nakamura K,Goto J,Kanazawa I: "Rapid Aggregate Formation of the Huntingtin N-Terminal Fragment Carrying and Expanded Polyglutamine Tract."Biochemical and Biophysical Research Communications. 256(2). 361-366 (1999)

Hazeki N、Nakamura K、Goto J、Kanazawa I：“携带亨廷顿蛋白 N 末端片段和扩展聚谷氨酰胺束的快速聚集体形成。”生物化学和生物物理研究通讯。

後藤 順: "Machado-Joseph disease (MJD)"Clinical Neuroscience. 17(4). 402-404 (1999)

Jun Goto：“马查多-约瑟夫病（MJD）”临床神经科学 17（4）（1999）。

後藤 順: "ハンチントン病" 綜合臨牀. 4・8(1). 100-103 (1999)

后藤淳：“亨廷顿病”Sogo 临床研究 4・8(1) 100-103 (1999)。