Leukaemia link to ‘sterile start’

AN over-sterile germ-free environment in the first year of life is one of the major causal factors behind childhood leukaemia, a controversial study suggests.

Coupled with unlucky genetics, it can leave a child vulnerable to common infections such as flu triggering the disease, says a leading expert.

Professor Mel Greaves, from the Institute of Cancer Research in London, claims the most common form of childhood leukaemia acute lymphoblastic leukaemia (ALL) - could be prevented by “priming” infants’ immune systems by exposing them to harmless bugs.

If the theory is backed by more evidence, a preventative treatment - possibly involving probiotic bacterial supplements - could be trialled in the next five years.

The research, published in the journal Nature Reviews Cancer, is based on a compilation of more than 30 years of work around the world investigating the origins of the disease.

Speaking at a press briefing in London, Prof Greaves said: “All the evidence is comprehensive. This is the bottom line for me - ALL is a paradox of progress in society.

“The research strongly suggests that ALL has a clear biological cause, and is triggered by a variety of infections in predisposed children whose immune systems have not been properly primed.”

The theory could explain why ALL, which affects white blood cells, is more prevalent in affluent societies where infants are shielded from infection. It may also be the reason why babies that are not breastfed, do not mix with other children in nurseries, are born by Caesarian section, or do not have siblings are more likely to develop the disease.

ALL is rare, affecting about one in 2,000 UK children per year, but can have a devastating impact on families despite a high cure rate.

Its likely causes have been debated for 100 years with a host of possible trigger factors proposed, including radiation, mobile phones, wi-fi, power-lines, and exposure to pollutant chemicals.

Dr Alasdair Rankin, research director at blood cancer charity Bloodwise, which funds Prof Greaves’ work, said: “If we could stop this type of leukaemia from happening in the first place it would be enormously exciting, but many questions need to be answered in the research lab before we will know for sure whether that could become a reality.”