Enzyme in babies’ blood linked to risk of sudden infant death syndrome

Scientists compared dried blood samples taken during the newborn heel prick test from 655 healthy babies, 26 babies who died from Sids and 41 babies who died in infancy from other causes. Photograph: Simon Dannhauer/Alamy

Scientists may have come a step closer to uncovering the causes for sudden infant death syndrome in a study that has been hailed as a significant advance by the British scientist whose work underpinned the Back to Sleep campaign of the 1990s.

The study is the first to identify a biochemical marker in the blood that is linked to the risk of Sids, sometimes called cot death, when an apparently healthy infant dies during their sleep. Although the test is not accurate enough to be used in newborn screening, it hints that abnormally low levels of a chemical linked to the brain’s arousal system could be involved in causing these babies to die suddenly in their sleep.