HLA Genotypes (In Japanese Patients)
Whilst the mutation of the RANBP2 gene has been confirmed to be associated with ANE, the involvement of HLA genotypes has not at this point. However, a recent study confirms the likelihood. ANE is estimated to be less than 20 people per year in Japan. ANE has been reported worldwide, but this disease is reported predominantly in children living in East Asian countries. The difference in occurence among various ethnic groups suggests the involvement of host genetic factors in ANE. Using 31 Japanese confirmed ANE patients a study was conducted in Japan and aimed for the first time to investigate genetic background of ANE within this ethnic group. Human leukocyte antigen (HLA) genotypes include HLA class I (HLA-A, -C and -B) and class II (HLA-DR, -DQ and -DP). These molecules play an important role in the immune response. The study focused on HLA genotypes as a predisposing factor to ANE based on the fact that the abnormal innate immune reaction was provoked by a preceding infection. In addition, HLA have been reported to be associated with various diseases susceptibility, such as autoimmune diseases and infectious diseases.
At the conclusion of the study there was enough evidence to support the above but due to the rarity of ANE the availability of statistics were limited. Further similar studies are required to confirm these findings. The data from this particular study suggests that specific HLA Genotypes are involved in the manner of development of ANE.