Spo11 is a protein-encoding gene conserved in all meiotic organisms [1]. Its essential function is to initiate meiotic recombination by inducing DNA double-strand breaks (DSBs), which is crucial for breaking up gene linkage and facilitating faithful chromosome segregation during gamete formation [1]. Meiotic recombination is a key pathway where Spo11 plays a central role, and its function is of great biological importance for sexual reproduction [1,3]. Genetic models, such as knockout (KO) models, are valuable for studying Spo11's function.

In budding yeasts lacking Spo11 (spo11∆), meiotic recombination initiation is deficient, leading to many inviable spores [2]. However, very rarely, all sets of 16 chromosomes are coincidentally assorted into gametes to form viable spores. In these viable spores of spo11∆ diploid, no homologous recombination was detected, and point mutations were fewer compared to wild-type. The spo11∆ viable spores either carried a complete diploid set of homolog pairs or haploid spores with a complete haploid set of homologs but aneuploidy in some chromosomes. There was also a chromosome-dependence in aneuploid incidence, with the chromosome length and the impact of dosage-sensitive genes having positive and negative influences respectively [2].

In conclusion, Spo11 is fundamental for meiotic recombination initiation through DSB induction, which is essential for proper chromosome segregation during gamete formation. The study of Spo11-less models, like the spo11∆ in budding yeasts, reveals its role in maintaining genetic integrity during meiosis. Although not directly related to diseases from the provided content, understanding Spo11's function may potentially provide insights into genetic disorders associated with abnormal meiotic recombination [1,2].