Mucopolysaccharidosis VI (MPS VI) is an autosomal recessive lysosomal storage disease caused by mutations in the arylsulfatase B gene (ARSB) and consequent deficient activity of ARSB, a lysosomal enzyme involved in glycosaminoglycan (s) (GAGs) metabolism. Here we present the results study of ARSB DNA analysis in MPS VI patients in the Russian Federation (RF) and other republics of Former Soviet Union. In a cohort of 68 patients (57 families) with MPS VI, a total of 28 different pathogenic alleles were found. The most prevalent nucleotide changes included c.194C>T (Ser65Phe) and c.454C>T (Arg152Trp). Five pathogenic alleles were novel, not previously reported (с.304C>G, c.533A>G, c.941T>C, c.447 456del10, С.990 1003del14). The nucleotide variant c.454C>T (Arg152Trp) was prevalent allele among Slavic Russian patients. The nucleotide variant c.194C>T (Ser65Phe) was found only in MPS VI families from the Republic of Dagestan. Based on the analysis of dry blood spots