Wnt5a plays a critical role in anal opening in mice at an early stage of embryonic development

Conditional knockout mouse study identifies E8 as the critical embryonic stage when Wnt5a signaling is required for anal opening and striated muscle complex formation. Findings demonstrate that Wnt5a knockout after E8 does not prevent anal opening, establishing a narrow developmental window for Wnt5a's essential role in anorectal development.