This study was designed as a reappraisal of the association between the TNF-376A promoter polymorphism and susceptibility to multiple sclerosis found in the Spanish population but not in other populations. With a new dataset of patients (n = 241) and control subjects (n = 288), the association was confirmed (p = 0.018). The authors' data suggest that this association is specific of the Spanish white (or related) population or, alternatively, that only studies in their population have the adequate statistical power because of the higher frequency of an extended, conserved haplotype carrying the TNF-376A allele.