title: Orosomucoid system: 17 additional orosomucoid variants and proposal for a new nomenclature.
abstract: There are two forms of orosomucoid (ORM) in the sera of most individuals. They are encoded by two separate but closely linked loci, ORM1 and ORM2. A number of variants have been identified in various populations. Duplication and nonexpression are also observed in some populations. Thus, the ORM system is very complicated and its nomenclature is very confusing. In order to propose a new nomenclature, ORM variants detected by several laboratories have been compared and characterized by isoelectric focusing (IEF) followed by immunoprinting. A total of 57 different alleles including 17 new ones were identified. The 27 alleles were assigned to the ORM1 locus, and the others to the ORM2 locus. The designations ORM*F1, ORM1*F2, ORM1*S and ORM2*M were adopted for the four common alleles instead of ORM1*1, ORM1*3, ORM1*2 and ORM2*1 (ORM2*A), respectively. The variants were designated alpha numerically according to their relative mobilities after IEF in a pH gradient of 4.5-5.4 with Triton X-100 and glycerol. For the duplicated genes a prefix is added to a combined name of two alleles, e.g. ORM1*dB9S. Silent alleles were named ORM1*Q0 and ORM2*Q0 conventionally. In addition, the effects of diseases to ORM band patterns after IEF are also discussed.
authors.affiliation: Department of Legal Medicine, Tottori University School of Medicine, Yonago, Japan.
authors.forename: I
authors.initials: I
authors.lastname: Yuasa
authors.forename: S
authors.initials: S
authors.lastname: Weidinger
authors.forename: K
authors.initials: K
authors.lastname: Umetsu
authors.forename: K
authors.initials: K
authors.lastname: Suenaga
authors.forename: G
authors.initials: G
authors.lastname: Ishimoto
authors.forename: B C
authors.initials: BC
authors.lastname: Eap
authors.forename: J C
authors.initials: JC
authors.lastname: Duche
authors.forename: P
authors.initials: P
authors.lastname: Baumann
mesh_terms: D000483:Alleles; D014644:Genetic Variation / Q000235:genetics*; D006801:Humans; D005810:Multigene Family / Q000235:genetics; D009961:Orosomucoid / Q000235:genetics*; D010375:Pedigree; D009626:Terminology as Topic
chemical_list: D009961:Orosomucoid