以聚合酶链反应（ＰＣＲ）技术检测不同年龄Ｂａｌｂ／ｃ小鼠脑细胞线粒体ＤＮＡ片段缺失与增龄的关系．发现老年鼠脑细胞线粒体３８６７ｂｐ片段缺失率为５０％；而断奶鼠与青年鼠均无此缺失片段出现；用鼠毛为材料进行无损伤检测亦获类似的结果．有人认为线粒体ＤＮＡ片段缺失率可作为生物衰老的一种生物学标志 Polymerase chain reaction (PCR) was used to detect the relationship between mitochondrial DNA deletion and aging in Balb / c mouse brain cells of different ages. It was found that the deletion rate of mitochondrial 3867 bp fragment in brain cells of aged rats was 50%, but no deletion fragments were found in the weaned mice and young mice. Similar results were obtained by using the rat hair as a non-destructive test. Some people think that mitochondrial DNA fragment deletion rate can be used as a bio-aging biological markers