Testing to identify babies more with Spinal Muscular Atrophy (SMA) is being rolled out in across Wessex.
The screening, part of a study run by Oxford University, will see 8000 babies tested over the next 14 months.
If identified at birth SMA can be treated and give newborns the best chance of living long and healthy lives.
The screening is administered via a prick to the heel, which allows scientists to test the blood of the baby for the genetic markers.
Mums giving birth at Salisbury Hospital, University Hospital Southampton, University Hospitals Dorset and Portsmouth Hospital will be invited to take part in the screening.