Bone marrow donor genetics is linked to risk of fungal infection

A bone marrow transplant can be a life-saving treatment for some
patients with leukaemia and some other forms of cancer. But sometimes recipients of bone marrow transplants, come down with invasive aspergillosis - a fungal infection that can be fatal.

Invasive aspergillosis occurs in up to 12% of bone marrow transplant recipients and one-year mortality rates range from 50% to 80%, making it "one of the leading infection-related causes of death," the researchers said.

Toll receptors are found on the surface of cells in the body's innate immune system and help to recognise invading pathogens. Because the toll-like receptors (or TLRs) play a key role in the immune response to fungal pathogens such as aspergillus, the researchers decided to see if genetic variation affected who came down with disease.

This study of bone marrow donors has shown that a particular genetic variation in TLR4, the gene for the toll receptor 4 is associated with a five fold increase of invasive aspergillosis in recipients of bone marrow - when the donor is unrelated. Recipients related to the donor do not appear to be at increased risk which is as yet unexplained, but the relatively small size of the groups in this study may be partially responsible. Further studies will be required to elucidate this. More information.

Read the paper by Buchud here.