目的：检测并分析miRNA在正常幼儿及不同年龄段白内障患者晶状体中的表达差异，初步探讨其在维持晶状体正常功能和不同年龄段白内障形成中的可能作用。

方法：使用stem-loop RT-PCR法检测正常幼儿和幼儿(先天性白内障)、中青年及老年(年龄相关性白内障)白内障患者晶状体中miRNA的表达情况，比较各组间miRNA表达差异。

结果：正常幼儿晶状体中miR-184表达量最高。与正常幼儿相比，白内障幼儿晶状体中miR-184、miR-182表达升高，miR-124、miR-204表达降低。与幼儿患者相比，中青年患者晶状体中miR-204、miR-124和let-7d表达升高，miR-184、miR-183和let-7a表达降低，而老年患者晶状体中所有被检测miRNA表达均有改变，其中miR-182、miR-204、miR-124表达均升高，miR-184、miR-181b、miR-183、miR-125b、let-7a/b/d表达均降低。

结论：正常幼儿及不同年龄段白内障患者晶状体中miRNA表达差异显著，部分miRNA与晶状体的正常形态、功能及某些病理状态相关，这为进一步研究miRNA在维持幼儿晶状体正常功能及不同年龄段白内障形成过程中的可能作用机制提供了理论依据。

METHODS: The different ages of miRNAs in lens were extracted and samples were divided into four groups: infant lens group(lens from non-ophthalmopathy infant), congenital cataract group(lens from cataract infant), young and middle-aged group(lens from young cataract patients)and senile group(lens from age-related cataract patients). The expression of the 10 miRNAs was detected in the four groups using stem-loop RT-PCR respectively.

RESULTS: In normal infant's lens, the expression of miR-184 was the highest. Compared with the normal infant's lens tissue, the miR-184 and miR-182 in congenital cataract patients increased, the miR-124 and miR-204 decreased. Compared with the children's lens with cataract, the expression of miR-204, 124 and let-7d in young and middle-aged cataract patients increased, while the expression of miR-184, 183 and let-7a decreased. In the lens of senile cataract patients, all of the 10 miRNAs changed. The expression of miR-182, 204, 124 increased, while miR-184, 181b, 183, 125b, let-7a/b/d decreased.

CONCLUSION: There are significant differences in the expression of miRNA in the lens of children and cataract patients of different ages. Some miRNAs are related to the normal morphology, function and certain pathological conditions of the lens. This study provided a theoretical basis of further study on the role of miRNAs in maintaining the normal function of the young children's lens and the formation of cataracts at different ages.