Dumoulin R, Sagnol I, Ferlin T, Bozon D, Stepien G, Mousson B
Laboratoire de Biochimie Pédiatrique, Hôpital Debrousse, Lyon, France.
Mol Cell Probes. 1996 Oct;10(5):389-91. doi: 10.1006/mcpr.1996.0053.
We have identified a new mitochondrial (mt) cytochrome b mutation in a 29-year-old man with progressive exercise muscle intolerance associated with a marked deficiency of complex III activity and a decreased amount of mitochondrial-encoded cytochrome b. This G to A transition at mtDNA position 15615 leads to the substitution (G290D) of a very highly conserved amino acid of cytochrome b during evolution. The mutant mtDNA was heteroplasmic (80% mutant) in patient muscle but was undetectable in blood from the patient and his healthy mother and sisters. A maternally inherited cytochrome b polymorphism was also identified in this patient. Molecular screening of 150 individuals showed that the G290D mutation associated with the described phenotype. We suggest that this molecular defect is the primary cause of the muscle disease in this patient.
我们在一名29岁男性中发现了一种新的线粒体（mt）细胞色素b突变，该患者患有进行性运动性肌肉不耐受，伴有显著的复合体III活性缺乏以及线粒体编码的细胞色素b含量减少。线粒体DNA位置15615处的这种G到A的转变导致了细胞色素b在进化过程中一个高度保守的氨基酸被替换（G290D）。突变的线粒体DNA在患者肌肉中是异质性的（80%突变），但在患者及其健康母亲和姐妹的血液中未检测到。在该患者中还鉴定出一种母系遗传的细胞色素b多态性。对150名个体的分子筛查表明，G290D突变与所述表型相关。我们认为这种分子缺陷是该患者肌肉疾病的主要原因。
