Scientists have created a mutant mouse embryo with six legs and no external genitals, highlighting the Tgfbr1 gene's role.

The inactivation of the Tgfbr1 gene resulted in the replacement of genital development with additional hindlimbs.

Findings offer significant insight into early animal development and may uncover evolutionary processes.

The research could have implications for understanding developmental diseases and human embryonic development.

This study is pivotal in embryonic research, with the potential to contribute to breakthroughs in health issues treatment.