Variations in a gene called IFRD1, linked to activity of white blood cells called neutrophils, may be involved in the severity of symptoms for patients with cystic fibrosis (CF) , according to a new US study published in Nature.
CF is a life-limiting inherited disease in which the lungs are filled with mucus and become clogged and damaged. It is caused by a defect in the CFTR gene. There are currently 8,000 people in the UK with the condition, and around one in twenty five people is a carrier. People with the disease typically die before they are 40 years old. There is as yet no cure - currently, medicines can only alleviate the symptoms.
An examination of DNA samples from 3,000 CF patients showed that small variations in the human IFRD1 gene were correlated with the severity of the disease.
In this study, they deleted the IFRD1 gene in mice, then exposed them to a bacterium called Pseudomonas aeruginosa. The mice took longer to remove the infection from their systems but suffered considerably less inflammatory damage. Their neutrophil activity was low, but other white blood cells behaved normally and overall their immune system functioned normally.
Dr Christopher Karp, of Cincinnati Children's Hospital in the US, led the study. Dr Karp said: 'It's possible that IFRD1 itself could become a target for treatment, but right now it's a signpost to pathways for further study. We want to find out what other genes and proteins IFRD1 interacts with, and how this is connected to inflammation in cystic fibrosis lung disease'.