biostudies-literatureDewey EBNational Cancer InstituteNCI NIH HHSNational Institute of General Medical SciencesNIGMS NIH HHSiyac164https://www.ebi.ac.uk/biostudies/studies/S-EPMC9836020biostudies-literatureUnknown223(1)Proper repair of DNA double-strand breaks is essential to the maintenance of genomic stability and avoidance of genetic disease. Organisms have many ways of repairing double-strand breaks, including the use of homologous sequences through homology-directed repair. While homology-directed repair is often error free, in single-strand annealing homologous repeats flanking a double-strand break are annealed to one another, leading to the deletion of one repeat and the intervening sequences. Studies in yeast have shown a relationship between the length of the repeat and single-strand annealing efficacy. We sought to determine the effects of homology length on single-strand annealing in Drosophila, as Drosophila uses a different annealing enzyme (Marcal1) than yeast. Using an in vivo single-straGeneticsThe effect of repeat length on Marcal1-dependent single-strand annealing in Drosophila.PMC9836020R35 GM1181271R35GM118127T32 CA217824Saghaey KWittmer MEKorda Holsclaw JDewey EBSekelsky JfalseThe effect of repeat length on Marcal1-dependent single-strand annealing in Drosophila.Proper repair of DNA double-strand breaks is essential to the maintenance of genomic stability and avoidance of genetic disease. Organisms have many ways of repairing double-strand breaks, including the use of homologous sequences through homology-directed repair. While homology-directed repair is often error free, in single-strand annealing homologous repeats flanking a double-strand break are annealed to one another, leading to the deletion of one repeat and the intervening sequences. Studies in yeast have shown a relationship between the length of the repeat and single-strand annealing efficacy. We sought to determine the effects of homology length on single-strand annealing in Drosophila, as Drosophila uses a different annealing enzyme (Marcal1) than yeast. Using an in vivo single-stra2023-01-01T00:00:00Z2023 Jan2026-03-27T15:46:12.937Z2025-04-06T13:10:04.284ZS-EPMC98360203630332210.1093/genetics/iyac164