title: Hb S-San Martin: a new sickling hemoglobin with two amino acid substitutions [β6(A3)Glu→Val;β105(G7)Leu→Pro] in an Argentinean family.
abstract: A new sickling hemoglobin (Hb) detected in an Argentinean family from San Martín, Buenos Aires, Argentina, is hereby described. Two mutations were identified on the same β-globin gene resulting in a new variant named Hb San Martin. One mutation was found on exon 1, corresponding to Hb S [β6Glu→Val, GAG>GTG] and the second one on exon 3 at β105(G7)Leu→Pro, CTC>CCC. The replacement of leucine by proline will likely impair the structure breaking helix G and causing instability of the molecule and the clinical manifestations typical of unstable Hbs. The mutation at β105 seemed to be a de novo one in our patients, arising on a previously mutated gene, due to the fact that Hb S is the most frequent structural variant.
authors.affiliation: Servicio de Hematología-Oncología, Hospital Prof. Dr. Juan P. Garrahan, Buenos Aires, Argentina. afeliutorres@yahoo.com
authors.forename: Aurora
authors.initials: A
authors.lastname: Feliu-Torres
authors.forename: Silvia Eandi
authors.initials: SE
authors.lastname: Eberle
authors.forename: Irma M
authors.initials: IM
authors.lastname: Bragós
authors.forename: Gabriela
authors.initials: G
authors.lastname: Sciuccati
authors.forename: Mara J
authors.initials: MJ
authors.lastname: Ojeda
authors.forename: Karina L
authors.initials: KL
authors.lastname: Calvo
authors.forename: María E
authors.initials: ME
authors.lastname: Voss
authors.forename: Arianna F
authors.initials: AF
authors.lastname: Pratti
authors.forename: Angela C
authors.initials: AC
authors.lastname: Milani
authors.forename: Mariana
authors.initials: M
authors.lastname: Bonduel
authors.forename: Lilian
authors.initials: L
authors.lastname: Díaz
authors.forename: Nélida I
authors.initials: NI
authors.lastname: Noguera
mesh_terms: D019943:Amino Acid Substitution; D001118:Argentina; D001483:Base Sequence; D002648:Child; D004252:DNA Mutational Analysis; D005192:Family Health; D006451:Hemoglobin, Sickle / Q000235:genetics*; D006455:Hemoglobins, Abnormal / Q000235:genetics*; D006801:Humans; D008297:Male; D008958:Models, Molecular; D009154:Mutation; D017433:Protein Structure, Secondary; D055544:beta-Globins / Q000737:chemistry / Q000235:genetics*
chemical_list: D006451:Hemoglobin, Sickle; D006455:Hemoglobins, Abnormal; D055544:beta-Globins; C556240:hemoglobin S-San Martin