Gosden J R, Lawrie S S, Gosden C M
Am J Hum Genet. 1981 Mar;33(2):243-51.
Satellite III DNA has been located by in situ hybridization in chromosomes 1, 3--5, 7, 9, 10, 13--18, 20--22, and Y and ribosomal DNA (rDNA) in the acrocentric chromosomes 13--15, 21, and 22. In the acrocentric chromosomes, the satellite DNA is located in the short arm. Here we report comparisons by in situ hybridization of the amount of satellite DNA in Robertsonian translocation and "normal variant" chromosomes with that in their homologs. In almost all dicentric Robertsonian translocations, the amount of satellite DNA is less than that in the normal homologs, but it is rarely completely absent, indicating that satellite DNA is located between the centromere and the nucleolus organizer region (NOR) and that the breakpoints are within the satellite DNA. The amount of satellite DNA shows a range of variation in "normal" chromosomes, and this is still more extreme in "normal variant" chromosomes, those with large short arm (p+ or ph+) generally having more satellite DNA than those with small short arms (p- or ph-). The cytological satellites are heterogeneous in DNA content; some contain satellite DNA, others apparently do not, and the satellite DNA content is not related to the size or intensity of fluorescence of the satellites. The significance of these variations for the putative functions of satellite DNA is discussed.
通过原位杂交技术，已确定卫星III DNA位于1、3 - 5、7、9、10、13 - 18、20 - 22号染色体以及Y染色体上，而核糖体DNA（rDNA）则位于13 - 15、21和22号近端着丝粒染色体上。在近端着丝粒染色体中，卫星DNA位于短臂上。在此，我们报告了通过原位杂交技术对罗伯逊易位染色体和“正常变异”染色体与其同源染色体中卫星DNA含量的比较。在几乎所有的双着丝粒罗伯逊易位中，卫星DNA的含量都低于正常同源染色体，但很少完全缺失，这表明卫星DNA位于着丝粒和核仁组织区（NOR）之间，且断点位于卫星DNA内部。卫星DNA的含量在“正常”染色体中呈现出一定范围的变化，而在“正常变异”染色体中这种变化更为极端，那些短臂较大（p +或ph +）的染色体通常比短臂较小（p -或ph -）的染色体含有更多的卫星DNA。细胞学上的卫星在DNA含量上是异质的；一些含有卫星DNA，另一些显然不含，且卫星DNA的含量与卫星的大小或荧光强度无关。本文讨论了这些变异对于卫星DNA假定功能的意义。
