Meiotic null MSH2 and SGS1 alleles in S. cerevisiae x S. uvarum hybrids result in near-haploid offspring with mixed parental chromosomal inheritance

Meiotic null MSH2 and SGS1 alleles in Saccharomyces cerevisiae × Saccharomyces uvarum hybrids do not increase hybrid fertility but enable recovery of near-haploid offspring with mixed parental chromosomes.

• Why it matters: F1 hybrid sterility in Saccharomyces clade hybrids is linked to mismatch repair recognizing divergent sequences during meiosis, yet prior conditional approaches can trade fertility for mutation accumulation.
• What they did: The meiotic null system was applied to S. cerevisiae × S. uvarum hybrids, and mass spore recovery plus flow cytometry were used to recover near-haploid offspring.
• The result: Although fertility is not improved, the recovered near-haploid, mixed-genome populations can be leveraged for phenotypic studies of hybrid genome effects on organismal fitness.