Looijenga L H, Oosterhuis J W, Smit V T, Wessels J W, Mollevanger P, Devilee P
Laboratory of Experimental Patho-Oncology, Dr. Daniel den Hoed Cancer Center, Rotterdam, The Netherlands.
Genomics. 1992 Aug;13(4):1125-32. doi: 10.1016/0888-7543(92)90027-p.
We have investigated the organization and complexity of alpha satellite DNA on chromosomes 10 and 12 by restriction endonuclease mapping, in situ hybridization (ISH), and DNA-sequencing methods. Alpha satellite DNA on both chromosomes displays a basic dimeric organization, revealed as a 6- and an 8-mer higher-order repeat (HOR) unit on chromosome 10 and as an 8-mer HOR on chromosome 12. While these HORs show complete chromosome specificity under high-stringency ISH conditions, they recognize an identical set of chromosomes under lower stringencies. At the nucleotide sequence level, both chromosome 10 HORs are 50% identical to the HOR on chromosome 12 and to all other alpha satellite DNA sequences from the in situ cross-hybridizing chromosomes, with the exception of chromosome 6. An 80% identity between chromosome 6- and chromosome 10-derived alphoid sequences was observed. These data suggest that the alphoid DNA on chromosomes 6 and 10 may represent a distinct subclass of the dimeric subfamily. These sequences are proposed to be present, along with the more typical dimeric alpha satellite sequences, on a number of different human chromosomes.
我们通过限制性内切酶图谱分析、原位杂交（ISH）和DNA测序方法，研究了10号和12号染色体上α卫星DNA的组织和复杂性。两条染色体上的α卫星DNA均呈现出基本的二聚体组织形式，在10号染色体上表现为6聚体和8聚体高阶重复（HOR）单元，在12号染色体上表现为8聚体HOR。虽然这些HOR在高严谨度ISH条件下显示出完全的染色体特异性，但在较低严谨度下它们识别相同的一组染色体。在核苷酸序列水平上，10号染色体的两个HOR与12号染色体上的HOR以及原位交叉杂交染色体上的所有其他α卫星DNA序列有50%的同一性，但6号染色体除外。观察到6号染色体和10号染色体衍生的α类序列之间有80%的同一性。这些数据表明，6号和10号染色体上的α类DNA可能代表二聚体亚家族的一个独特亚类。这些序列被认为与更典型的二聚体α卫星序列一起存在于许多不同的人类染色体上。
