Linear regression analysis was performed to establish the correlation between age of onset and disability on one hand, and the size of EcoRI fragment, on the other.

• 采用线性回归法分析患者发病年龄、丧失行走能力的年龄与EcoRI片段长度的相关关系，采用t检验比较易位和非易位组及不同性别患者的片段长度及发病年龄差异。