Molecular characteristics

A spelling mistake within a gene is called a mutation. Our genes are present in pairs in all the cells of our body; we inherit one gene of the pair from our mother and the other is inherited from our father. We usually need both copies of the DNMT3A gene to be working to grow and develop.

In TBRS, there is a mutation in one of the gene copies and so it does not work optimally. A range of different spelling mistakes, or mutations, cause TBRS but the commonest type is called a missense mutation which describes the substitution of a single letter of the DNA alphabet or code.