Digest: Do weakly deleterious mutations exacerbate reproductive and health challenges in species with prolonged bottlenecks?

Do weakly deleterious mutations contribute to the reproductive and health challenges of bottlenecked species? Peers et al. (2025). investigated the role of prolonged low effective population size in cheetahs (A. jubatus) and its implications in the accumulation of pseudogenes. They identified 65 cheetah-specific premature termination codons, and four of which (DEFB116, ARL13A, CFAP119, and NT5DC4) were linked to male fertility and immune deficiencies. These findings reveal how pseudogenization may contribute to fertility challenges and reproductive health decline.