Surprising new research has found that spinal muscular atrophy, traditionally thought of as a neuromuscular disease, may also affect the immune system.

In a research published in the journal Human Molecular Genetics, Dr. Rashmi Kothary’s group found that mouse models of the disease had dramatically smaller spleens with an abnormal inner structure. The spleen is an important part of the immune system that removes bacteria and viruses from the blood. In addition, the researchers saw that SMA impaired the development of white blood cells called T–cells in the thymus.

The team found that they could prevent these defects from happening in mouse models of SMA by genetically introducing a human SMN gene. Further research is required to see if these immune defects exist in SMA patients, and what the implications may be for treatment.