Children with Bloom syndrome, an inherited DNA repair disorder, can present with symmetric growth deficiency (pre- or postnatal onset) and a sun-sensitive facial ‘butterfly’ rash.

Affected patients will have a variety of distinctive features and a progressive reduction in the production of normal blood cells in the bone marrow, which results in pancytopenia and an increased chance of developing certain cancers.

Pancytopenia is a condition in which a person has too few red blood cells, white blood cells and platelets. In some children presenting with pancytopenia, there will be a genetic cause.