Scientists Track Early Genetic Origins of Childhood Leukemia in Womb

A new study published in the scientific journal PNAS uncovers clues to the origin of leukemia during childhood in two pairs of identical twins. Researchers hope that by tracing the early genetic origins of childhood leukemia, they could help develop a new cancer drug.

One of the most common cancers diagnosed in children is leukemia, and it affects a third of young cancer sufferers. In the U.K., every year 100 children die due to this disease.

"The research team at the ICR has been at the forefront of studies into leukaemia in twins that have developed a deeper understanding of the types and sequence of events that lead to blood cells becoming cancerous. This study has used state-of-the-art emerging technologies to still further understand how cancer develops. Although the study was performed in young twins, it reveals processes that are relevant to adult leukaemias, which are far more common, and also potentially relevant to other cancers," professor Chris Bunce, Research Director at Leukaemia & Lymphoma Research, said in a press statement.

In order to identify the mutations that trigger the diseases in the womb, a study led by scientists at The Institute of Cancer Research (ICR) investigated this link by sequencing the three billion letter genomes of two pairs of identical twins with leukemia.

The researchers took genetic samples from two sets of identical twins who were victims of acute lymphoblastic leukemia (ALL). They noticed a common leukemia-causing gene known as ETV6-RUNX1 that was generated in the womb. This was generated by the exchange of genetic material between chromosomes. It was an important mutation that was divided by the twins. They suspect that it triggered a generic change that led to leukemia.

Mutation initially occurs in one cell in one twin, and these cells consisting of the mutation spread to the other twin through the shared circulation that is present in the womb.

On the whole, a total of 22 mutations were exhibited by two twins, but the twins never shared any of these mutations. As a result, it accumulates after birth as the disease spreads.

In the second pair of identical twins, the mutation was inherited from parents, known as NF1, therefore inclining them toward leukemia.  

Such kinds of studies produce novel methods to target the root of cancer and help to understand better how the disease develops over a period of time.