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Background We studied the prevalence of neuromyelitis optica spectrum disorder (NMOSD) and multiple sclerosis (MS) in Indigenous populations of Australia and New Zealand with the aim of assessing potential differences. Methods Cases of possible NMOSD and MS were collected from Australia and New Zealand. Clinical details, MR imaging, and serologic results were used to apply 2015 IPND diagnostic criteria for NMOSD and 2010 McDonald criteria for MS. Frequencies of self-determined ethnic ancestry were calculated for confirmed NMOSD, suspected NMOSD, and MS. Prevalence rates for NMOSD and MS according to ancestry were compared. Results There were 75 cases with NMOSD, 89 with suspected NMSOD, and 101 with MS. NMOSD cases were more likely to have Asian, Indigenous, or Other ancestry compared to suspected NMOSD or MS. There were no differences in the clinical phenotype of NMOSD seen in Indigenous compared to European ancestry populations. Per 100,000, the prevalence estimate for NMOSD in people with Māori ancestry was 1.50 (95% CI 0.52–2.49) which was similar to those with Asian ancestry 1.57 (95% CI 1.15–1.98). NMOSD prevalence in Australian Aboriginal and Torres Strait Islander populations was 0.38 (95% CI 0.00–0.80) per 100,000. Conclusion The prevalence of NMOSD in the Māori population is similar to South East Asian countries, reflecting their historical origins. The prevalence of MS in this group is intermediate between those with South East Asian and European ancestry living in New Zealand. Both NMOSD and particularly MS appear to be uncommon in the Indigenous populations of Australia.

Multiple Sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system. The risk of developing MS is strongly influenced by genetic predisposition, and over 100 loci have been established as associated with susceptibility. However, the biologically relevant variants underlying disease risk have not been defined for the vast majority of these loci, limiting the power of these genetic studies to define new avenues of research for the development of MS therapeutics. It is therefore crucial that candidate MS susceptibility loci are carefully investigated to identify the biological mechanism linking genetic polymorphism at a given gene to the increased chance of developing MS. MERTK has been established as an MS susceptibility gene and is part of a family of receptor tyrosine kinases known to be involved in the pathogenesis of demyelinating disease. In this study we have refined the association of MERTK with MS risk to independent signals from both common and low frequency variants. One of the associated variants was also found to be linked with increased expression of MERTK in monocytes and higher expression of MERTK was associated with either increased or decreased risk of developing MS, dependent upon HLA-DRB1*15:01 status. This discordant association potentially extended beyond MS susceptibility to alterations in disease course in established MS. This study provides clear evidence that distinct polymorphisms within MERTK are associated with MS susceptibility, one of which has the potential to alter MERTK transcription, which in turn can alter both susceptibility and disease course in MS patients.

Multiple sclerosis (MS) is a chronic relapsing-remitting inflammatory disease of the central nervous system characterized by oligodendrocyte damage, demyelination and neuronal death. Genetic association studies have shown a 2-fold or greater prevalence of the HLA-DRB1*1501 allele in the MS population compared with normal Caucasians. In discovery cohorts of Australasian patients with MS (total 2941 patients and 3008 controls), we examined the associations of 12 functional polymorphisms of P2X7, a microglial/macrophage receptor with proinflammatory effects when activated by extracellular adenosine triphosphate (ATP). In discovery cohorts, rs28360457, coding for Arg307Gln was associated with MS and combined analysis showed a 2-fold lower minor allele frequency compared with controls (1.11% for MS and 2.15% for controls, P = 0.0000071). Replication analysis of four independent European MS case-control cohorts (total 2140 cases and 2634 controls) confirmed this association [odds ratio (OR) = 0.69, P = 0.026]. A meta-analysis of all Australasian and European cohorts indicated that Arg307Gln confers a 1.8-fold protective effect on MS risk (OR = 0.57, P = 0.0000024). Fresh human monocytes heterozygous for Arg307Gln have >85% loss of 'pore' function of the P2X7 receptor measured by ATP-induced ethidium uptake. Analysis shows Arg307Gln always occurred with 270His suggesting a single 307Gln-270His haplotype that confers dominant negative effects on P2X7 function and protection against MS. Modeling based on the homologous zP2X4 receptor showed Arg307 is located in a region rich in basic residues located only 12 Å from the ligand binding site. Our data show the protective effect against MS of a rare genetic variant of P2RX7 with heterozygotes showing near absent proinflammatory 'pore' function.

• Multiple sclerosis (MS) is an autoimmune disease of the central nervous system with a multifactorial aetiology and highly variable natural history. • A growing understanding of the immunopathogenesis of the condition has led to an expanding array of therapies for this previously untreatable disease. • While a cure for MS remains elusive, the potential to reduce inflammatory disease activity by preventing relapses and minimising disease progression is achievable. • The importance of early treatment in minimising long-term disability is increasingly recognised. • Most of the newer, more effective therapies are associated with risks and practical problems that necessitate an active management strategy and continuous vigilance. • While the initiation of these therapies is likely to remain the responsibility of neurologists, other specialist physicians and general practitioners will be involved in the identification and management of adverse effects.

In Part 2 of this three part review of multiple sclerosis (MS) treatment with a particular focus on the Australian and New Zealand perspective, we review the newer therapies that have recently become available and emerging therapies that have now completed phase III clinical trial programs. We go on to compare the relative efficacies of these newer and emerging therapies alongside the existing therapies. The effectiveness of β-interferon in the treatment of different stages and the different disease courses of MS is critically reviewed with the conclusion that the absolute level of response in term of annualised relapse rates (where relapses occur) and MRI activity are similar, but are disappointing in terms of sustained disability progression for progressive forms of the disease. Finally we review the controversial area of combination therapy for MS. Whilst it remains the case that we have no cure or means of preventing MS, we do have a range of effective therapies that when used appropriately and early in the disease course can have a significant impact on short term and longer term outcomes.

In this third and final part of our review of multiple sclerosis (MS) treatment we look at the practical day-to-day management issues that are likely to influence individual treatment decisions. Whilst efficacy is clearly of considerable importance, tolerability and the potential for adverse effects often play a significant role in informing individual patient decisions. Here we review the issues surrounding switching between therapies, and the evidence to assist guiding the choice of therapy to change to and when to change. We review the current level of evidence with regards to the management of women in their child-bearing years with regards to recommendations about treatment during pregnancy and whilst breast feeding. We provide a summary of recommended pre- and post-treatment monitoring for the available therapies and review the evidence with regards to the value of testing for antibodies which are known to be neutralising for some therapies. We review the occurrence of adverse events, both the more common and troublesome effects and those that are less common but have potentially much more serious outcomes. Ways of mitigating these risks and managing the more troublesome adverse effects are also reviewed. Finally, we make specific recommendations with regards to the treatment of MS. It is an exciting time in the world of MS neurology and the prospects for further advances in coming years are high.

Multiple sclerosis (MS) is a potentially life-changing immune mediated disease of the central nervous system. Until recently, treatment has been largely confined to acute treatment of relapses, symptomatic therapies and rehabilitation. Through persistent efforts of dedicated physicians and scientists around the globe for 160 years, a number of therapies that have an impact on the long term outcome of the disease have emerged over the past 20 years. In this three part series we review the practicalities, benefits and potential hazards of each of the currently available and emerging treatment options for MS. We pay particular attention to ways of abrogating the risks of these therapies and provide advice on the most appropriate indications for using individual therapies. In Part 1 we review the history of the development of MS therapies and its connection with the underlying immunobiology of the disease. The established therapies for MS are reviewed in detail and their current availability and indications in Australia and New Zealand are summarised. We examine the evidence to support their use in the treatment of MS.

Multiple sclerosis (MS) is a common chronic inflammatory disease of the central nervous system. Susceptibility to the disease is affected by both environmental and genetic factors. Genetic factors include haplotypes in the histocompatibility complex (MHC) and over 50 non-MHC loci reported by genome-wide association studies. Amongst these, we previously reported polymorphisms in chromosome 12q13-14 with a protective effect in individuals of European descent. This locus spans 288 kb and contains 17 genes, including several candidate genes which have potentially significant pathogenic and therapeutic implications. In this study, we aimed to fine-map this locus. We have implemented a two-phase study: a variant discovery phase where we have used next-generation sequencing and two target-enrichment strategies [long-range polymerase chain reaction (PCR) and Nimblegen's solution phase hybridization capture] in pools of 25 samples; and a genotyping phase where we genotyped 712 variants in 3577 healthy controls and 3269 MS patients. This study confirmed the association (rs2069502, P = 9.9 × 10(-11), OR = 0.787) and narrowed down the locus of association to an 86.5 kb region. Although the study was unable to pinpoint the key-associated variant, we have identified a 42 (genotyped and imputed) single-nucleotide polymorphism haplotype block likely to harbour the causal variant. No evidence of association at previously reported low-frequency variants in CYP27B1 was observed. As part of the study we compared variant discovery performance using two target-enrichment strategies. We concluded that our pools enriched with Nimblegen's solution phase hybridization capture had better sensitivity to detect true variants than the pools enriched with long-range PCR, whilst specificity was better in the long-range PCR-enriched pools compared with solution phase hybridization capture enriched pools; this result has important implications for the design of future fine-mapping studies.

The aim of this work was to evaluate sex differences in the incidence of multiple sclerosis relapses; assess the relationship between sex and primary progressive disease course; and compare effects of age and disease duration on relapse incidence. Annualized relapse rates were calculated using the MSBase registry. Patients with incomplete data or <1 year of follow-up were excluded. Patients with primary progressive multiple sclerosis were only included in the sex ratio analysis. Relapse incidences over 40 years of multiple sclerosis or 70 years of age were compared between females and males with Andersen-Gill and Tweedie models. Female-to-male ratios stratified by annual relapse count were evaluated across disease duration and patient age and compared between relapse-onset and primary progressive multiple sclerosis. The study cohort consisted of 11 570 eligible patients with relapse-onset and 881 patients with primary progressive multiple sclerosis. Among the relapse-onset patients (82 552 patient-years), 48,362 relapses were recorded. Relapse frequency was 17.7% higher in females compared with males. Within the initial 5 years, the female-to-male ratio increased from 2.3:1 to 3.3:1 in patients with 0 versus ≥4 relapses per year, respectively. The magnitude of this sex effect increased at longer disease duration and older age (P < 10(-12)). However, the female-to-male ratio in patients with relapse-onset multiple sclerosis and zero relapses in any given year was double that of the patients with primary progressive multiple sclerosis. Patient age was a more important determinant of decline in relapse incidence than disease duration (P < 10(-12)). Females are predisposed to higher relapse activity than males. However, this difference does not explain the markedly lower female-to-male sex ratio in primary progressive multiple sclerosis. Decline in relapse activity over time is more closely related to patient age than disease duration.

Objective: Higher latitude, lower ultraviolet exposure, and lower serum 25-hydroxyvitamin D (25OHD) correlate with higher multiple sclerosis (MS) prevalence, relapse rate, and mortality. We therefore evaluated the effects of high-dose vitamin D2 (D2) in MS. Method(s): Adults with clinically active relapsing-remitting MS (RRMS) were randomized to 6 months' double-blind placebo-controlled high-dose vitamin D2, 6,000 IU capsules, dose adjusted empirically aiming for a serum 25OHD 130-175 nM. All received daily low-dose (1,000 IU) D2 to prevent deficiency. Brain MRIs were performed at baseline, 4, 5, and 6 months. Primary endpoints were the cumulative number of new gadolinium-enhancing lesions and change in the total volume of T2 lesions. Secondary endpoints were Expanded Disability Status Scale (EDSS) score and relapses. Result(s): Twenty-three people were randomized, of whom 19 were on established interferon or glatiramer acetate (Copaxone) treatment. Median25OHDrose from54to69nM(low-dose D2) vs59to120 nM (high-dose D2) (p = 0.002). No significant treatment differences were detected in the primary MRI endpoints. ExitEDSS,after adjustment for entryEDSS,washigher following high-doseD2than following low-doseD2(p=0.05). There were4relapses with high-doseD2vs none with low-doseD2(p=0.04). Conclusion(s): We did not find a therapeutic advantage in RRMS for high-dose D2 over low-dose D2 supplementation. Classification of evidence: This study provides Class I evidence that high-dose vitamin D2 (targeting 25OHD 130-175 nM), compared to low-dose supplementation (1,000 IU/d), was not effective in reducing MRI lesions in patients with RRMS. Copyright © 2011 by AAN Enterprises, Inc.

The medical treatment of severe Parkinson's disease is presently problematical and neural transplantation has been proposed as an additional therapy. While functional improvement in animal models of Parkinson's disease has been reported following neural grafting, the treatment of human Parkinsonian patients by adrenal medulla autografting into the neostriatum has produced little clinical improvement overall, and is associated with significant morbidity. Although recent grafting of human foetal dopaminergic neurons has shown more promise, many of the case reports lack rigorous assessment and long term follow-up. Further laboratory experimentation in animal models, particularly primates, to ascertain the mechanism of action of the grafts, the optimal sites for grafting, and the immunological responses to grafting, is essential. The future success of neural transplantation for Parkinson's disease may depend on the development of novel strategies such as the use of growth factors to aid cell survival, regulate neurotransmitter levels and promote connectivity. However, at present, the clinical application of neural transplantation for Parkinson's disease is premature.

Multiple sclerosis is a common disease of the central nervous system in which the interplay between inflammatory and neurodegenerative processes typically results in intermittent neurological disturbance followed by progressive accumulation of disability1. Epidemiological studies have shown that genetic factors are primarily responsible for the substantially increased frequency of the disease seen in the relatives of affected individuals2, 3, and systematic attempts to identify linkage in multiplex families have confirmed that variation within the major histocompatibility complex (MHC) exerts the greatest individual effect on risk4. Modestly powered genome-wide association studies (GWAS)5, 6, 7, 8, 9, 10 have enabled more than 20 additional risk loci to be identified and have shown that multiple variants exerting modest individual effects have a key role in disease susceptibility11. Most of the genetic architecture underlying susceptibility to the disease remains to be defined and is anticipated to require the analysis of sample sizes that are beyond the numbers currently available to individual research groups. In a collaborative GWAS involving 9,772 cases of European descent collected by 23 research groups working in 15 different countries, we have replicated almost all of the previously suggested associations and identified at least a further 29 novel susceptibility loci. Within the MHC we have refined the identity of the HLA-DRB1 risk alleles and confirmed that variation in the HLA-A gene underlies the independent protective effect attributable to the class I region. Immunologically relevant genes are significantly overrepresented among those mapping close to the identified loci and particularly implicate T-helper-cell differentiation in the pathogenesis of multiple sclerosis.

Multiple sclerosis (MS) is a debilitating, chronic demyelinating disease of the central nervous system affecting over 2 million people worldwide. The TAM family of receptor tyrosine kinases (TYRO3, AXL and MERTK) have been implicated as important players during demyelination in both animal models of MS and in the human disease. We therefore conducted an association study to identify single nucleotide polymorphisms (SNPs) within genes encoding the TAM receptors and their ligands associated with MS. Analysis of genotype data from a genome-wide association study which consisted of 1618 MS cases and 3413 healthy controls conducted by the Australia and New Zealand Multiple Sclerosis Genetics Consortium (ANZgene) revealed several SNPs within the MERTK gene (Chromosome 2q14.1, Accession Number NG_011607.1) that showed suggestive association with MS. We therefore interrogated 28 SNPs in MERTK in an independent replication cohort of 1140 MS cases and 1140 healthy controls. We found 12 SNPs that replicated, with 7 SNPs showing p-values of less than 10−5 when the discovery and replication cohorts were combined. All 12 replicated SNPs were in strong linkage disequilibrium with each other. In combination, these data suggest the MERTK gene is a novel risk gene for MS susceptibility.

Recent association studies in multiple sclerosis (MS) have identified and replicated several single nucleotide polymorphism (SNP) susceptibility loci including CLEC16A, IL2RA, IL7R, RPL5, CD58, CD40 and chromosome 12q13–14 in addition to the well established allele HLA-DR15. There is potential that these genetic susceptibility factors could also modulate MS disease severity, as demonstrated previously for the MS risk allele HLA-DR15. We investigated this hypothesis in a cohort of 1006 well characterised MS patients from South-Eastern Australia. We tested the MS-associated SNPs for association with five measures of disease severity incorporating disability, age of onset, cognition and brain atrophy. We observed trends towards association between the RPL5 risk SNP and time between first demyelinating event and relapse, and between the CD40 risk SNP and symbol digit test score. No associations were significant after correction for multiple testing. We found no evidence for the hypothesis that these new MS disease risk-associated SNPs influence disease severity.

We conducted an association study across the human leukocyte antigen (HLA) complex to identify loci associated with multiple sclerosis (MS). Comparing 1927 SNPs in 1618 MS cases and 3413 controls of European ancestry, we identified seven SNPs that were independently associated with MS conditional on the others (each ). All associations were significant in an independent replication cohort of 2212 cases and 2251 controls () and were highly significant in the combined dataset (). The associated SNPs included proxies for HLA-DRB1*15:01 and HLA-DRB1*03:01, and SNPs in moderate linkage disequilibrium (LD) with HLA-A*02:01, HLA-DRB1*04:01 and HLA-DRB1*13:03. We also found a strong association with rs9277535 in the class II gene HLA-DPB1 (discovery set , replication set , combined ). HLA-DPB1 is located centromeric of the more commonly typed class II genes HLA-DRB1, -DQA1 and -DQB1. It is separated from these genes by a recombination hotspot, and the association is not affected by conditioning on genotypes at DRB1, DQA1 and DQB1. Hence rs9277535 represents an independent MS-susceptibility locus of genome-wide significance. It is correlated with the HLA-DPB1*03:01 allele, which has been implicated previously in MS in smaller studies. Further genotyping in large datasets is required to confirm and resolve this association.

Multiple sclerosis (MS) is a genetically complex autoimmune disease. To dissect further the involvement of four recent identified MS susceptibility genes (KIAA0350, IL2RA, RPL5 and CD58) in disease pathogenesis, we genotyped 94 haplotype-tagging single nucleotide polymorphisms (SNPs) from these loci in 1146 MS cases and 1309 controls. Seven newly-typed SNP variants were nominally associated with risk of MS, and one SNP (rs791589) in the first intron of the IL2RA gene remained associated after adjustment for rs2104286 genotype, a previously reported SNP association. These data provide further evidence of allelic heterogeneity at the IL2RA locus and point to the existence of at least two independent MS susceptibility alleles.

To identify multiple sclerosis (MS) susceptibility loci, we conducted a genome-wide association study (GWAS) in 1,618 cases and used shared data for 3,413 controls. We performed replication in an independent set of 2,256 cases and 2,310 controls, for a total of 3,874 cases and 5,723 controls. We identified risk-associated SNPs on chromosome 12q13–14 (rs703842, P = 5.4 times 10-11; rs10876994, P = 2.7 times 10-10; rs12368653, P = 1.0 times 10-7) and upstream of CD40 on chromosome 20q13 (rs6074022, P = 1.3 times 10-7; rs1569723, P = 2.9 times 10-7). Both loci are also associated with other autoimmune diseases1, 2, 3, 4, 5. We also replicated several known MS associations (HLA-DR15, P = 7.0 times 10-184; CD58, P = 9.6 times 10-8; EVI5-RPL5, P = 2.5 times 10-6; IL2RA, P = 7.4 times 10-6; CLEC16A, P = 1.1 times 10-4; IL7R, P = 1.3 times 10-3; TYK2, P = 3.5 times 10-3) and observed a statistical interaction between SNPs in EVI5-RPL5 and HLA-DR15 (P = 0.001).

A recent genome-wide association study (GWAS) conducted by the International Multiple Sclerosis Genetics Consortium (IMSGC) identified a number of putative MS susceptibility genes. Here we have performed a replication study in 1134 Australian MS cases and 1265 controls for 17 risk-associated single nucleotide polymorphisms (SNPs) reported by the IMSGC. Of 16 SNPs that passed quality control filters, four, each corresponding to a different non-human leukocyte antigen (HLA) gene, were associated with disease susceptibility: KIAA0350 (rs6498169) P=0.001, IL2RA (rs2104286) P=0.033, RPL5 (rs6604026) P=0.041 and CD58 (rs12044852) P=0.042. There was no association (P=0.58) between rs6897932 in the IL7R gene and the risk of MS. No interactions were detected between the replicated IMSGC SNPs and HLA-DRB1*15, gender, disease course, disease progression or age-at-onset. We used a novel Bayesian approach to estimate the extent to which our data increased or decreased evidence for association with the six most-associated IMSGC loci. These analyses indicated that even modest P-values, such as those reported here, can contribute markedly to the posterior probability of ‘true’ association in replication studies. In conclusion, these data provide support for the involvement of four non-HLA genes in the pathogenesis of MS, and combined with previous data, increase to genome-wide significance (P=3 × 10−8) evidence of an association between KIAA0350 and risk of disease.