细胞周期抑制性基因ANA在唐氏综合征患者脑组织过量表达

Cell-cycle negative regulatory gene ANA is over-expressed in the brain tissues of patients with Down syndrome

目的分析唐氏综合征(Down syndrome,DS)胎儿脑组织21号染色体(Chr21)基因的表达,探讨DS脑病变的分子机制。方法采用优化的半定量RT-PCR法,以B2M为内参,检测了7个Chr21基因在DS胎儿及同龄对照胎儿大脑皮层及小脑组织中的表达。结果Chr21基因DYRK1A,SYNJ1,PCP4(purkinje cell protein4gene),C21orf5,C21orf2和C21orf106的表达在DS胎儿大脑皮层及小脑组织较正常对照均没有明显改变。ANA(abundantin neuroepithelium area)基因表达在DS胎儿小脑无明显改变,但在DS胎儿大脑皮层的表达显著升高。结论细胞周期抑制性基因ANA的过表达可能与DS患者脑组织神经元细胞密度低有关。

Objective： To investigate the expression level of genes located in chromosome 21 in the brain tissues of Down syndrome （DS）. Methods： An optimized semi-quantitative RT-PCR method was used to evaluate the expression levels of seven genes encoded in chromosome 21 in fetal cortex brain and cerebellum of DS and the control at the end of 20 weeks of gestation. B2M was used as internal reference to normalize cell loss. Results： The expression levels of 6 genes in cortex and cerebellum, including DYRKIA, SYNJI, PCP4, C21orfS, C21orf2 and C21orfl06, were comparable between DS and the control. ANA, a cell-cycle negative regulatory gene, was over-expressed dramatically in the cortex but not in the cerebellum of DS. Conclusion： Over-expression of ANA may contribute to the reduction of neuronal density in DS brain.