Gene That Protects Against Malaria May Increase Lupus Susceptibility

WASHINGTON, DC -- April 13, 2010 -- A gene variant suspected of helping protect people of Asian and African descent from malaria may increase their susceptibility to lupus, according to a study published Proceedings of the National Academy of Sciences.

The study was led by Kenneth Smith, Cambridge Institute for Medical Research and Department of Medicine, University of Cambridge School of Clinical Medicine, Addenbrooke's Hospital, Cambridge, United Kingdom.

For the study, Dr. Smith and colleagues genotyped nearly 5,000 patients with lupus and malaria from Kenya, Hong Kong, and the United Kingdom.

The researchers searched and tested patients' DNA for a FCGR2B gene variant known to be more common in Asians and sub-Saharan Africans.

Previous studies had linked a polymorphism of the gene to an immune system response that may enhance lupus susceptibility and malaria resistance.

The researchers report that the FCGR2B polymorphism appeared more frequently in patients with lupus who were from Hong Kong than in controls,
 and less frequently in Kenyan children with severe malaria compared with Kenyan children in the general population.

The results are consistent with well-established observations that lupus is more prevalent in people of Asian and African descent than in Caucasians, and may support the authors' theory that malaria's high mortality rate could be driving an increased susceptibility to autoimmune disease in specific ethnic groups.


SOURCE: Proceedings of the National Academy of Sciences