线粒体基因组的五个新的多态性

目的：通过分析线粒体基因组序列，进一步了解中国人线粒体基因多态性特点。方法：在4个中国汉族个体的线粒体基因组全长16569bp进行分段PCR和荧光测序的基础上，针对发现的7个未报道的新单碱基变异，以识别变异的限制性内切酶和通过引物变动人工增;加识别位点的方法，对这些变异进行100个正常人对照绵PCR－限制酶切分析。结果：发现5个未经MITOMAP收录或发表的线粒体基因序列变化C298T，C638G，C3206T，A5323T，均属多态性位点，基因频率分别为：17．65％，32．04％，62．77％，33．33％和32．26％。结论：5个新发现的多态性位点，1个位于线粒体基因组调控区（C298T），2个位于编码蛋白MTCO1区（A6323G，C6326T），另外两个分别位于编码12S和16S的rRNA区（C638G和C3206T），为在中国人中首先报道的多态性。

Five de novo forms of polymorphisms first found in Chinese mitochondrial genome

Objective To know more polymorphic changes in mitochondrial genome in Chinese. Method PCR and sequencing of the 16 569 bp long mtDNA of the white blood cel l DNA were conducted on 4 Chinese children, 3 with Rett syndrome and one normal. PCR and Re striction endonuclease digest, including artificial created restriction site (ACRS), were done on 100 normal controls in the light of the 7 newly discovered single base s ubstitution sites. Result Five point mutations, C298T, C638G, C3206T, A6323G and C6326T, neithe r appearing in MITOMAP database nor reported in literature before, were identifi ed in Chinese people with the frequencies of 17.65%, 32.04%, 62.77%, 33.33% and 32.26%. Other two point mu tations, C737T and C9860T, were found only in patients with Rett syndrome. Conclusion The five sequence changes newly found in mitochondrial genome of Chin ese are de novo kinds of polymorphism.