Unable to unwind, but not unhealthy

When chromosomes swap genetic material during meiosis – a process that generates crossovers – precision is everything. Double-strand DNA breaks are essential for chromosome alignment and segregation, but too many can threaten genome stability. The right balance fuels genetic diversity while preserving genome integrity. An enzyme long thought to inhibit crossover formation is now revealed to be a crucial architect of the process. In a new study published in Nucleic Acids Research, researchers from the Jantsch-Plunger lab discovered that the Bloom helicase, HIM-6, an enzyme that unwinds DNA, plays a previously unrecognized non-catalytic role in supporting successful meiosis in nematodes.