Development of novel marker loci of rat by detecting variable number of tandem repeats using polymerase chain reaction.

在近交系大鼠s&W中表现出变异的遗传标记的鉴定是高度期望的。本研究采用聚合酶链反应（PCR）技术检测大鼠IL-3基因可变数目串联重复序列（VNTR），建立了VNTR的标记位点，并对IL-3基因VNTR的多态性进行了研究。在28个品系的近交系大鼠中检测到4种类型的扩增片段。基因定位分析表明IL-3基因座与位于大鼠10号染色体上的Gh、RatNGFRR和RatABPG基因座连锁。结论：IL-3基因位于大鼠第10号染色体上，其顺序为：Gh-RatNGFRR-RatABPG-IL-3。大鼠精囊分泌（SVS）IV基因也含有一个VNTR。用PCR扩增该区域，在24株菌株中发现3个等位基因。这种变异以常染色体共显性方式分离。我们将这个位点命名为Svs-4。Svs-4位点与其他位点之间的连锁分析表明，该位点与Svp-1和a位点紧密连锁，属于大鼠连锁群IV。因此，Svs-4位点属于连锁群IV。在DNA数据库中检索了含有二核苷酸重复序列的大鼠微卫星序列。在获得的微卫星序列中，通过PCR分析了几个序列，以检查近交系大鼠品系的大小变化。所有微卫星序列大小可变，表明微卫星位点可作为大鼠遗传连锁分析的有效标记，VNTR位点可作为构建大鼠遗传连锁图谱的有力工具。利用VNTR基因座进行连锁分析，构建大鼠特定染色体图谱的工作正在取得进展。

Identification of genetic markers exhibiting variations among inbred rat s&W are highly desired. In the present study, some marker loci were established by detecting variable number of tandem repeats(VNTR)using polymerase chain reaction(PCR).A polymorphism of VNTR in rat interleukin-3 gene, Il-3, was investigated by PCR. There were detected four types of the amplified fragments in 28 inbred rat strains. Searegation analysis revealed the linkage between Il-3 locus and Gh, RatNGFRR, or RatABPG loci, which are located on rat chromosome 10. It was thus concluded that the Il-3 locus is located on rat chromosome 10 with following order of loci ; Gh-RatNGFRR-RatABPG-Il-3.The rat seminal vesicle secretion(SVS)IV gene also contains a VNTR. This region was amplified using PCR and tnree alleles were found in 24 strains. This variation segregated as an autosomal codominant manner. We designated this locus as Svs-4. Analysis of linkages between the Svs-4 locus and other loci revealed that this locus is closely linked to Svp-1 and a loci, which belong to rat linkage group IV. Therefor the Svs-4 loci is revealed to belong to the linkage group IV.Microsatellite sequences of rat containing dinucleotide repeats were searched in DNA databases. Among the obtained microsatellites sequences, several sequences were analyzed by PCR to examine size variation in inbred rat strains. All of the microsatellite sequences were variable in size, indicating that the microsatellite loci should be useful marker for linkage analyses of the rat.It was thus concluded that the VNTR loci should be powerful tool for constructing linkage map of the rats. We are now progress in constructing the maps of particular chromosomes of the rats by linkage analyses using the VNTR loci.