微型鼠的骨密度分析及其突变基因的初步定位

发布时间：2018-05-13 01:01

本文选题：微型鼠 + ENU诱变　；参考：《延边大学》2006年硕士论文

【摘要】：为进一步研究基因突变与侏儒症的关系，利用化学物质乙基亚硝基脲(N-ethyl-N-nitrosourea，ENU)人工诱变了BALB／c小鼠，经传代产生了一种侏儒症形态的小鼠，并命名这种变异小鼠为微型鼠(Small Body Size mouse，SBS)。经遗传分析发现微型鼠表现常染色体隐性遗传特性。微型鼠在出生1日龄时，其形态与正常BALB／c小鼠肉眼不易区分，但其体重与正常BALB／c小鼠比较差异显著。1周龄后的微型鼠经肉眼观察其形态可与正常BALB／c小鼠区分，并且体重差异更加显著。本试验不但检测了微型鼠的体重及骨密度变化，而且利用微卫星遗传标记通过遗传连锁分析对突变基因进行了初步定位。试验中随机选择了30只微型鼠和24只正常BALB／c小鼠，从出生到14周龄进行长期的观察并记录体重变化；并且另外随机选择了5只微型鼠和5只正常小鼠，分别在3周龄和6周龄进行骨密度检测。为了实现对突变基因的初步定位，本研究首先利用回交试验法培育出了142只回交后代[(SBS×C57BL／6J)F_1×SBS]F_2，再次通过PCR法对19条常染色体上的79个微卫星遗传标记进行详细的筛选，从而完成遗传连锁分析。试验结果表明，，从出生到14周龄微型鼠的体重显著低于同龄的正常BALB／c小鼠的体重，尤其在3周龄时其体重是正常BALB／c小鼠体重的43.7％，差异极显著(P＜0.001)。在骨密度检测的结果中，本研究发现微型鼠在3周龄和6周龄时的骨密度都明显低于同龄正常BALB／c小鼠的。遗传连锁分析结果表明，突变基因(sbs)初步定位在第10条染色体上，选用本染色体上与侏儒病表型相关基因产后体重增长因子(Pbwg9)和过氧化体生物合成因子(Pex7)最近的微卫星D10Mit283标记引物扩增，在142只F_2代中只发生一例交换，表明Pbwg9基因和Pex7基因是本实验中侏儒症突变的强有力的候选基因。
[Abstract]:In order to further study the relationship between gene mutation and dwarfism, BALB/c mice were induced by the chemical substance ethyl-N-nitrosourea- (ENUU), and a dwarfism morphologic mouse was produced by subculture. The mutated mice were named as small Body Size mousetrap (SBSN). Genetic analysis revealed that micromice showed autosomal recessive genetic characteristics. At 1 day of birth, the morphology of miniature mice was not easily distinguished from that of normal BALB/c mice, but their body weight was significantly different from that of normal BALB/c mice. 1 weeks after birth, the morphology of miniature mice could be distinguished from that of normal BALB/c mice by naked eye observation. And the weight difference is even more significant. Not only the body weight and bone mineral density of micromice were detected, but also the mutated genes were preliminarily located by genetic linkage analysis using microsatellite genetic markers. In the experiment, 30 miniature mice and 24 normal BALB/c mice were randomly selected for long-term observation from birth to 14 weeks of age and body weight changes were recorded, and 5 miniature mice and 5 normal mice were randomly selected. Bone mineral density (BMD) was measured at 3 weeks and 6 weeks of age, respectively. In order to locate the mutated genes, we first selected 142 backcross progenies [SBS 脳 C57BL/6J)F_1 脳 SBS] F2 by backcross test, and then screened 79 microsatellite genetic markers on 19 autosomes by PCR method. Thus, genetic linkage analysis was completed. The results showed that the body weight of the miniature mice from birth to 14 weeks was significantly lower than that of the normal BALB/c mice of the same age, especially at the age of 3 weeks, the body weight was 43.7 of the normal BALB/c mice, and the difference was very significant (P < 0.001). The results of bone mineral density (BMD) test showed that the BMD of miniature mice at the age of 3 weeks and 6 weeks was significantly lower than that of the normal BALB/c mice of the same age. The results of genetic linkage analysis showed that the mutant gene was located on chromosome 10. Microsatellite D10Mit283 marker primers were used to amplify the gene associated with dwarf disease phenotypic postpartum weight gain factor (Pbwg9) and peroxisome biosynthesis factor (Pex7) on this chromosome. Only one exchange occurred in 142 F2s. The results showed that Pbwg9 gene and Pex7 gene were strong candidate genes for dwarfism mutation in this experiment.
【学位授予单位】：延边大学
【学位级别】：硕士
【学位授予年份】：2006
【分类号】：R-332

【参考文献】