Systematic review finds MSTN gene editing in livestock yields multiplicative trait effects with health challenges

This systematic review synthesized evidence on the pleiotropic effects of myostatin (MSTN) gene editing across multiple livestock species, including cattle, swine, sheep, poultry, and aquatic species. The review examined outcomes related to growth performance, carcass quality, meat quality, metabolic homeostasis, reproductive performance, and animal health and welfare. The primary finding was that MSTN editing has a multiplicative effect on trait alterations, though the specific effect sizes, absolute numbers, and statistical significance were not reported. The analysis also identified a series of associated health challenges associated with the intervention, though details on serious adverse events, discontinuations, and tolerability were not provided.

The review's authors note that the technology's impact is systemic, generating a spectrum of trade-offs that are often species specific. Key limitations include the observation that the focus on the remarkable double-muscle phenotype has often overshadowed a systematic examination of its concomitant effects. The review also cites inherent limitations and ethical issues of current editing techniques. Information on study funding or potential conflicts of interest was not reported.

Regarding practice relevance, the authors conclude that responsible application of MSTN gene editing hinges on multitrait balancing strategies to simultaneously secure productivity and sustainability in animal agriculture. The evidence, as a review of existing studies, does not establish causality. Clinicians should interpret these findings as a high-level synthesis pointing to both potential benefits and significant, systemic welfare trade-offs that require careful species-specific evaluation.