Southampton DNA research explains Bridport boy's infections
Doctors have used a pioneering test to pinpoint the genetic cause of a 10-year-old boy's mystery illnesses.
Mathew Knight, from Bridport, Dorset, gave a blood sample after being admitted to Southampton Children's Hospital with an infected hip.
Tests revealed a genetic mutation which harmed his immunity to certain types of bacteria.
A genetic research director said the speed of the diagnosis - three weeks - was "like sci-fi dreaming a year ago".
Mathew's problems began at just three months old, when he reacted badly to a BCG vaccination and required the first of several hospital admissions in his life.
The University Hospital Southampton (UHS) said tests revealed a deletion in the gene interferon gamma receptor 1 (IFNGR1).
Dr William Rae, a fellow in clinical immunology at UHS, said: "Due to an inability to respond to interferon gamma correctly, his immune system couldn't function properly, which is why he has been so susceptible.
"This diagnosis means he can receive the best possible treatment, directly targeting the problem with regular injections to boost his immunity against mycobacteria."
The test was part of a wider study, the Exome project, in Southampton and Salisbury, which aims to create a diagnostic test for all genes associated with diseases.
Professor Saul Faust, a director of genetic research at the University of Southampton, said: "Mathew's case is incredible. To go from a sample to molecular genetic diagnosis in three weeks was sci-fi-like dreaming even just a year ago.
"We are now in a really exciting time for medical and scientific breakthroughs, with initiatives such as the 100,000 Genomes Project meaning tests like this could become a routine part of healthcare in the future."
The 100,000 Genomes Project is a UK project which which could lead to targeted therapies for cancer and other diseases.