Assessment of hypermutable ssDNA in meiosis

This study investigates how meiosis, a fundamental process responsible for halving the genome to produce gametes, contributes to genetic mutations through the formation of hypermutable single-stranded DNA (ssDNA). By utilizing the human cytidine deaminase APOBEC3A (A3A) to specifically mark ssDNA in Saccharomyces cerevisiae, the study uncovers long tracts of hypermutable ssDNA accumulate at sites of recombination during meiosis. These ssDNA regions are highly prone to mutagenesis and have a potential to result in mutation clusters spanning up to 30 kb and contain over 100 mutations per meiotic product.