The HLA DRB1*03:01 allele is associated with NMO regardless of the NMO-IgG status in Brazilian patients from Rio de Janeiro

- The HLA DRB1*03:01 allele confer susceptibility to NMO regardless the NMO-IgG status.
- The presence of the HLA DRB1*03:01 allele did not influence morbidity or mortality.
- Different patterns of HLA class II allele association allow to discriminate between NMO and MS.

The aim of this study was to analyze the HLA class II alleles in neuromyelitis optica (NMO) and MS patients from Rio de Janeiro to clarify whether the pattern of genetic predisposition in NMO is different from the one seen in MS or whether it is possible to determine specific alleles of susceptibility or resistance. The DR3 haplotype was over represented in NMO while the DR15 was over represented in MS. The HLA-DRB1*03:01 allele was associated with NMO regardless the NMO-IgG status but did not influence the long term disability. The comparison of the allele and haplotype frequencies significantly discriminated patients with NMO vs. MS.

Although a graphical abstract is optional, its use is encouraged as it draws more attention to the online article. The graphical abstract should summarize the contents of the article in a concise, pictorial form designed to capture the attention of a wide readership. s should be submitted as a separate file in the online submission system.178