Creating a six-legged mouse for the first time

In Portugal, scientists have made a groundbreaking discovery by creating a 6-legged mouse embryo with an extra pair of hind legs instead of external genitalia. Mois├ęs Mallo, a biologist at the Gulbenkian Institute of Sciences in Oerias, Portugal, and his team are studying the receptor protein Tgfbr1 which plays a crucial role in embryonic development.

The Tgfbr1 gene codes for a transforming growth factor beta type 1 receptor protein that is involved in cellular responses like cell growth and division. Mutations in this gene can increase the risk of skin cancer. The researchers discovered that inactivating the Tgfbr1 gene in mouse embryos led to the development of hind legs instead of external genitalia. This finding indicates that Tgfbr1 dictates whether structures develop into genitals or legs.

The study’s results reveal that Tgfbr1 regulates other genes’ activity and can lead to mice with extra legs and no external genitalia. The research team plans to investigate how Tgfbr1 and related genes affect other systems such as cancer metastasis, and whether similar processes occur in reptiles with double penises.

The embryos used in the study were collected from mice aged 3-6 months. The research team dissected the embryos without distinguishing between male and female embryos since their external genitalia do not differ. Further research will focus on understanding the broader implications of the Tgfbr1 gene in development and disease.

This fascinating discovery has significant implications for our understanding of genetic regulation during embryonic development, potentially leading to new therapeutic approaches for diseases caused by mutations in this gene.

By Sophia Gonzalez

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