title: Molecular characterization and phenotypical study of β-thalassemia in Tucumán, Argentina.
abstract: The main hereditary hemoglobin (Hb) disorder in Argentina is β-thalassemia (β-thal). Molecular studies performed in the center of the country exhibited a marked prevalence of the codon 39 (C > T) and IVS-I-110 (G > A) mutations. The northwest region of Argentina has a different demographic history characterized by an important Spanish influx. Seventy-one β-thal carriers attending the Instituto de Bioquímica Aplicada, Tucumán, Argentina, were investigated for β-globin gene mutations by real-time polymerase chain reaction (RT-PCR). To examine the genotype-phenotype relationship, mean corpuscular volume (MCV), mean corpuscular Hb (MCH) and Hb A2 were measured. In order to recognize β-thal, Mentzer Index, Shine & Lal and Red Cell Distribution Width Index (RDWI), were calculated. The ethnic background of subjects revealed that 82.0% of the population was of Italian, Spanish and Arab origin. Seven mutations were detected: codon 39 (45.0%), IVS-I-1 (G > A) (22.5%), IVS-I-110 (16.3%), IVS-II-1 (G > A) (4.1%), IVS-I-1 (G > T) (2.0%), IVS-I-6 (T > C) (2.0%) and IVS-II-745 (G > C) (2.0%). In three families (6.1%), β-thal mutations were not determined. These results differed from other Argentinian studies because at present codon 39 and IVS-I-1 are the most prevalent; MCV, MCH and Hb A2 did not correlate with the type of mutation (β(0)/β(+)). Values of MCV (67.0 fL) and Hb A2 (4.85%) were unable to discriminate between them. Significant differences (p < 0.05) in MCV, MCH and Shine & Lal were observed between the undetermined group and the three most common mutations. These data show different patterns of β-thal mutations in the center and northwest regions of Argentina. Differences might represent the influence of Spanish immigration.
authors.affiliation: Instituto de Bioquímica Aplicada, Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán , Tucumán , Argentina and.
authors.forename: Sandra S
authors.initials: SS
authors.lastname: Lazarte
authors.forename: María E
authors.initials: ME
authors.lastname: Mónaco
authors.forename: Ana C
authors.initials: AC
authors.lastname: Haro
authors.forename: Cecilia L
authors.initials: CL
authors.lastname: Jiménez
authors.forename: Myriam E
authors.initials: ME
authors.lastname: Ledesma Achem
authors.forename: Blanca A
authors.initials: BA
authors.lastname: Issé
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001118:Argentina / Q000453:epidemiology / Q000208:ethnology; D002648:Child; D002675:Child, Preschool; D004909:Erythrocyte Indices; D005260:Female; D006455:Hemoglobins, Abnormal / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D017354:Point Mutation; D017086:beta-Thalassemia / Q000097:blood / Q000201:enzymology / Q000208:ethnology / Q000235:genetics
chemical_list: D006455:Hemoglobins, Abnormal
keywords: Argentina; genotype-phenotype correlation; β-thalassemia (β-thal) mutations