Correlation Between the Prevalence of Myasthenia Gravis and the Frequency of Class II Human Leucocyte Antigen Alleles in Various Geographical Locations Around the World.

Myasthenia gravis (MG) is an autoimmune condition characterised by muscle weakness due to antibodies produced against post-synaptic receptors. The impact of MG can be significant, especially with an ageing population. Human leukocyte antigens (HLA) are polymorphic genes associated with autoimmune conditions. Establishing the HLA alleles associated with MG may aid in the diagnosis, screening and early management of individuals at risk of MG. This research aims to establish the class II HLA alleles associated with the prevalence of MG in various regions of the world and identify the alleles that could predispose to the condition. A Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flow chart and various databases including, Scopus and PubMed as well as other sources were used to find appropriate papers on HLA class II alleles associated with MG and the prevalence of MG in various countries. The frequency of selected HLA alleles in selected regions were obtained from the website, allelefrequencies.net. From this, a correlation coefficient and p-value were calculated to investigate whether the frequency of MG and the prevalence of HLA alleles had a significant association.  The results highlighted two HLA alleles, DRB1*04:04 and DRB1*03, to have a significant positive association with the prevalence of MG. The frequency of the alleles showed regional variation, with European countries, particularly Northern Europe, exhibiting the highest frequencies. A significant positive correlation between HLA-DRB1*04:04 and DRB1*03 showed with the prevalence of MG, highlighting these alleles as a possible cause of the disease. Screening for these alleles, particularly in Northern Europe, may help identify individuals susceptible to MG.