Dear P H, Cook P R
Sir William Dunn School of Pathology, University of Oxford, UK.
Nucleic Acids Res. 1993 Jan 11;21(1):13-20. doi: 10.1093/nar/21.1.13.
We have devised a simple method for ordering markers on a chromosome and determining the distances between them. It uses haploid equivalents of DNA and the polymerase chain reaction, hence 'happy mapping'. Our approach is analogous to classical linkage mapping; we replace its two essential elements, chromosome breakage and segregation, by in vitro analogues. DNA from any source is broken randomly by gamma-irradiation or shearing. Markers are then segregated by diluting the resulting fragments to give aliquots containing approximately 1 haploid genome equivalent. Linked markers tend to be found together in an aliquot. After detecting markers using the polymerase chain reaction, map order and distance can be deduced from the frequency with which markers 'co-segregate'. We have mapped 7 markers scattered over 1.24 Mbp using only 140 aliquots. Using the 'whole-genome' chain reaction, we also show how the approach might be used to map thousands of markers scattered throughout the genome. The method is powerful because the frequency of chromosome breakage can be optimized to suit the resolution required.
我们设计了一种简单的方法来对染色体上的标记进行排序并确定它们之间的距离。该方法使用DNA的单倍体等价物和聚合酶链反应，因此称为“hapmap（快乐图谱）”。我们的方法类似于经典的连锁图谱分析；我们用体外类似物取代了其中两个关键要素，即染色体断裂和分离。任何来源的DNA通过γ射线照射或剪切随机断裂。然后通过稀释产生的片段来分离标记，以得到含有大约1个单倍体基因组等价物的等分试样。连锁的标记往往会在一个等分试样中同时出现。使用聚合酶链反应检测标记后，可以根据标记“共分离”的频率推断图谱顺序和距离。我们仅使用140个等分试样就对分布在1.24兆碱基对范围内的7个标记进行了定位。使用“全基因组”链反应，我们还展示了该方法如何用于对散布在整个基因组中的数千个标记进行定位。该方法很强大，因为染色体断裂的频率可以优化以适应所需的分辨率。
