eQTL结合ASE分析显示帕金森病相关基因Lrrk2表达受顺式作用调控

富亮氨酸重复激酶2（Lrrk2）基因与家族性及散发性帕金森病(Parkinson′s disease, PD)密切相关，但其作用机制仍不十分清楚.本文以单核苷酸多态性(single nucleotide polymorphism, SNP)为切入点，对其调控机制进行研究. 以近交系C57BL/6J (B6)和DBA/2J (D2)小鼠杂交1代小鼠为实验动物，借助基因表达数量性状基因座(expression quantitative trait loci, eQTL)分析技术,结合等位基因特异性表达（allele specific expression difference, ASE）技术,验证帕金森病相关基因Lrrk2的顺式调控机制. eQTL分析显示，Lrrk2基因所在的位置有1个具有显著统计学意义（LRS值≥20）的顺式调节基因座.针对Lrrk2基因外显子区域错意突变SNP的ASE分析得出： rs50098646位点在cDNA水平上G∶A两碱基比值偏离1∶1，与gDNA水平中G∶A两碱基比值差异显著（P<0.01），表达受顺式作用调节. 本研究结果表明,Lrrk2基因的表达受到顺式作用的调控.

eQTL and ASE Analyses Indicate cis-regulation in Parkinson’s Disease-related Lrrk2 Expression

The leucine-rich repeat kinase 2 (Lrrk2) gene is closely related with Parkinsons disease (PD), and the abnormal expression of Lrrk2 gene is the important cause which causes familial and sporadic PD. The expression mechanism of Lrrk2 remains unknown. In this study, we used near inbred strains C57BL/6J(B6) and DBA/2J(D2)F1 mice as expression animal, and used single nucleotide polymorphism（SNP）as entry point to explore the regulatory mechanism of the gene expression. The cis-regulation mechanism of Lrrk2 gene expression was determined by expression quantitative trait loci（eQTL）to build initially the regulatory pathway of gene expression by genetic genomics method. The authenticity of difference in Lrrk2 gene expression was validated by the allele specific expression difference（ASE）technology. The results showed that there was a statistically significant (LRS≥20) cis-regulating loci (cis-QTL) in chromosome 15 location of Lrrk2 gene on the eQTL mapping of Lrrk2. The ASE results revealed that the ratio of G∶A expression on the SNP rs50098646 site had dramatic change in cDNA and gDNA, respectively (P<001). This indicates that the regulatory mechanism of Lrrk2 gene expression was mainly determined by cis-regulation.