These charts show the mutated DNA of two children with acute lymphoblastic leukaemia. The coloured bands illustrate where large areas of the children’s DNA, called chromosomes (1–22, X and Y), once broke apart and stuck back together in an unnatural arrangement (chromosome 5 joined to chromosome 18, for example), triggering their disease. There are vital clues here as to when this event happened: the children are twins, and their identically jumbled DNA suggests that the cancer originated before birth, in the womb. Other DNA mutations (shown with purple, blue or red dashes around the circumference of the rings) are unique to each twin, showing how their conditions diverged and developed separately after they were born. Unravelling the early time-lines of childhood cancers is vital for pre-natal diagnosis and post-natal treatment, especially as the disease can develop to be just as individual as we are.
Written by John Ankers
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.
BPoD is also available in Catalan at www.bpod.cat with translations by the University of Valencia.