MUTATIONS IN THE COL1A1 GENE OF TYPE I COLLAGEN

成骨不全(OI)I型是遗传性疾病中最温和的一种 脆性骨病。来自受影响个体的成纤维细胞产生 大约是结构正常的I型胶原预期量的一半 这是其组成链之一Pro`1合成减少的结果。 基因组DNA的聚合酶链式反应-单链扩增 构象多态性分析(SSCP)与变性 梯度凝胶电泳法(DGGE)已被用于鉴定突变 轻度成骨患者I型胶原COLIAI基因的研究 不完美。一名个体被鉴定为单核苷酸 改变5‘供体剪接位点的替换。逆转录-聚合酶链式反应 这样就可以克隆和测序这一片段，以评估 该突变对剪接的影响。此外，多态还具有 在以前未检测到的内含子2区域中检测到 描述。对这种多态的表征正在进行中。 未来的研究将包括分析细胞的调节机制。 I型胶原与OI患者的首例突变筛查 COLIAI基因的内含子，其中的调控元件 之前确认过的。这些突变对基因表达的影响 将在成纤维细胞和成骨细胞系中进行研究。

Osteogenesis imperfecta (OI) type I is the mildest form of inherited brittle bone disease. Fibroblasts from affected individuals produce about half the expected amount of structurally normal type I collagen as a result of decreased synthesis of pro`1, one of its constituent chains. PCR amplification of genomic DNA followed by single-stranded conformational polymorphism electrophoresis (SSCP) and denaturing gradient gel electrophoresis (DGGE) has been used to identify mutations in the COLIAI gene of type I collagen in patients with mild Osteogenesis imperfecta. One individual was identified with a single nucleotide substitution which alters the 5' donor splice site. RT-PCR was done on this fragment so that cDNA can be cloned and sequenced to evaluate the effect of this mutation on splicing. In addition, a polymorphism has been detected in the region of intron 2 which has not been previously described. Characterization of this polymorphism is in progress. Future studies will involve analysis of the regulatory mechanisms of type I collagen and screening OI patients for mutations in the first intron of the COLIAI gene, where regulatory elements have been previously identified. The effect of these mutations on gene expression will be studied in fibroblast and osseous cell lines.