PRDM9 is a zinc finger protein that binds DNA at specific locations in the genome where it trimethylates histone H3 at lysines 4 and 36 at surrounding nucleosomes. During meiosis in many species, including humans and mice where PRDM9 has been most intensely studied, these actions determine the location of recombination hotspots, where genetic recombination occurs. In addition, PRDM9 facilitates the association of hotspots with the chromosome axis, the site of the programmed DNA double-strand breaks (DSBs) that give rise to genetic exchange between chromosomes. In the absence of PRDM9 DSBs are not properly repaired. Collectively, these actions determine patterns of genetic linkage and the possibilities for chromosome reorganization over successive generations.

PRDM9是一种锌指蛋白，可与基因组中特定位置的DNA结合，并在周围核小体的赖氨酸4和36处将组蛋白H3三甲基化。在许多物种的减数分裂过程中，包括对PRDM9进行了最深入研究的人类和小鼠，这些作用决定了发生重组基因的重组热点的位置。另外，PRDM9促进了热点与染色体轴的关联，染色体轴是编程的DNA双链断裂（DSB）的位点，引起了染色体之间的遗传交换。在缺少PRDM9的情况下，无法正确修复DSB。这些作用共同决定了遗传连锁的模式以及连续几代染色体重组的可能性。