• Question: Why do some babies come on earth with an extra bit of skin or a missing body part?

    Asked by Paka Maka the 1st (Adira) to Yinka, Stéphane on 13 Mar 2018.
    • Photo: Stéphane Berneau

      Stéphane Berneau answered on 13 Mar 2018:

      During embryo development, there is a specific family of genes that are responsible for the structure and location of body part: HOMEOBOX genes.
      These genes are very well conserved between species.
      However, abnormalities can happen due to a mutation or the protein regulated by the homeobox genes expression does not respond.
      Bardet-Biedl syndrome (BBS) is a genetic condition that impacts multiple body systems. People suffering from this syndrome tend to have an extra digit on their hands and/or feet.

      Missing a body part can also be linked to lifestyle and medication. Thalidomide is a medication that was prescribed for certain types of cancers and was authorized for pregnant women. Complications were observed at birth, children were born with deformities of all four limbs. It was a big scandal.

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