Thousands of babies in six areas across the country, including Birmingham, are to be screened for five rare diseases which - undetected - cause severe disability.
Around 430,000 newborns will be tested in the year long study, which starts today, and about 16 children are expected to be diagnosed and treated early enough to help them live normal lives.
The study will help determine if undiagnosed illnesses can be prevented from developing in children.
When a baby is about five days old, a midwife will collect a sample of blood by pricking the baby’s heel.
The card is sent off for analysis and parents receive the results of the blood spot test within a couple of months.
Babies will be screened at Birmingham Childrens Hospital, Sheffield, Leeds, Great Ormond Street, Manchester Childrens Hospital and Guy's and St Thomas'.
Sickle cell disease: an inherited blood disorder. Treating babies will help prevent serious illness.
Cystic fibrosis: a life-limiting inherited disorder that affects the internal organs, especially the lungs and digestive system.
Phenylketonuria (PKU): a very rare condition that can cause mental disability (but is treatable once diagnosed).
Congenital hypothyroidism: another rare condition that can lead to impaired growth and mental development. Treated babies can develop normally.
Medium-chain acyl Co-A dehydrogenase deficiency (MCADD): a rare, but potentially life-threatening inherited disorder, where fat cannot be broken down by the body as well as usual. Babies with MCADD develop normally, but recognising the condition early enables parents to make sure they eat regularly and avoid serious illness.