We studied the expression of C9orf72 gene in pathologies associated with hexanucleotide repeats expansion in this gene: frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). The study included 7 patients with hexanucleotide repeats expansion in the C9orf72 gene and 9 patients of the control group. The expression of C9orf72 mRNA was evaluated in blood leukocytes by real-time PCR. Methylation of CpG-sites in C9orf72 promotor region was evaluated by DNA sequencing after bisulfite conversion. A 2-fold decrease in the C9orf72 gene expression was found in patients with hexanucleotide repeats expansion in comparison with controls, though the difference did not reach statistical significance due to small sample size. The highest expression was shown for ALS in comparison with FTD and FTD-ALS phenotype. A trend to inverse correlation between C9orf72 mRNA level and promoter methylation of this gene as well as between mRNA level and age of disease onset was demonstrated.

中文翻译：

---

C9orf72 基因在额颞叶痴呆和肌萎缩侧索硬化中的表达

我们研究了 C9orf72 基因在与该基因中六核苷酸重复扩增相关的病理中的表达：额颞叶痴呆 (FTD) 和肌萎缩侧索硬化 (ALS)。该研究包括 7 名 C9orf72 基因六核苷酸重复扩增的患者和 9 名对照组患者。C9orf72 mRNA 在血液白细胞中的表达通过实时 PCR 进行评估。在亚硫酸氢盐转化后，通过 DNA 测序评估 C9orf72 启动子区域中 CpG 位点的甲基化。与对照组相比，六核苷酸重复扩增患者的 C9orf72 基因表达降低了 2 倍，但由于样本量小，差异没有达到统计学显着性。与 FTD 和 FTD-ALS 表型相比，ALS 的表达最高。