小鼠DNA的限制性片段长度多态性分析

RESTRICTION FRAGMENT LENGTH POLYMORPHISM OF MICE USING MYO PROBE

用人类肌红蛋白基因内含子中３３ｂｐ的小卫星ＤＮＡ重复序列为探针，经ｐＢＲ３２２的ＥｃｏＲＩ正向测序引物和α３２ＰｄＣＴＰ在ＴａｑＤＮＡ聚合酶作用下做合成标记，与６种小鼠的ＤＮＡ限制性片段杂交。结果显示，每个品系平均出现可分辨带纹在１３条以上，不同品系小鼠间的杂交带纹表现出高度的多态性。多态性带纹主要分布在６～２３ｋｂ区段；同一近交系的不同个体间的带纹特点及分布完全一致；Ｃ５７与ＡＫＲ及二者与其他鼠间的亲缘关系更远；随机两种品系鼠间的平均相关机率为４１×１０－８。因此，认为此方法可用于不同品系近交系小鼠的亲缘关系鉴别和遗传监测。

Myo probe constructed from human myoglobin gene intron, which hybridized to hypervariable minisatellite regions of human DNA to produce DNA fingerprints, has been shown to reveal similar hypervariability in two strains of mice as that in human. Recently, we have analyzed the DNA polymorphism of 6 strains of mice (BALB/c, DBA, C57, CBA, AKR and Kunming) using this probe. According to the hybridizing patterns,the probability estimates were: for each strain the numbers of mean identifiable polymorphism bands were over 13; among the strains, highly polymorphism were shown; the mean probability that fragments detected by Myo in one strain would be also present in another strain was 0.24 3 8 ×0 28 3.5 ×0.34 6.5 =4.1×10 -8 . There are higher polymorphism between C57 and AKR, and also between these two strains and the rest of the other 6 strains. The DNA polymorphism analysis by Myo probe suggest that this probe is powerful for distinguishing different strains and for estimating genetic relationships, and seems to be suitable for genetic monitoring and linkage analysis.