Tissue Antigens ISSN 0001-2815 BRIEF COMMUNICATION HNA-1a, HNA-1b and HNA-1c gene frequencies in Argentineans C. D. de La Vega Elena 1,2 , N. Nogue ´s 3 , A. Ferna ´ ndez Montoya 4 , S. Oyonarte 4 , E. Solis 1 & E. Mun ˜ iz-Dı´az 3 1 Servicio de Medicina Transfusional, Hospital Italiano Garibaldi, Rosario, Argentina 2 Departamento de Bioquı ´mica Clı ´nica, Facultad de Bioquı ´mica y Ciencias Biolo ´ gicas, Universidad Nacional del Litoral (U.N.L.), Santa Fe, Argentina 3 Banc de Sang i Teixits, Barcelona, Spain 4 Centro Regional de Transfusio ´ n Sanguı ´nea de Granada-Almeria, Granada, Spain Key words Argentinean population; gene frequencies; HNA; human neutrophil antigens Correspondence Carlos Daniel de La Vega Elena, PhD Servicio de Medicina Transfusional Hospital Italiano Garibaldi Virasoro 1249 (2000) Rosario Santa Fe Argentina Tel: 154 342 457 5215 Fax: 154 342 457 5221 e-mail: daniel.delavega@yahoo.com Received 16 January 2008; revised 12 February 2008; accepted 28 February 2008 doi: 10.1111/j.1399-0039.2008.01034.x Abstract Human neutrophil antigens (HNA) are polymorphic structures located in the neutrophil membrane. The neutrophil-specific antigens HNA-1a (NA1), 1b (NA2) and 1c (SH) are well-recognized allotypic forms of FcgRIIIb and the most frequent targets of neutrophil alloantibodies. The aim of this study was to determine the gene frequencies of the neutrophil-specific antigens belonging to the HNA-1 system in blood donors and Toba Amerindians from Rosario, Argentina. Two hundred and eighteen unrelated healthy Argentinean blood donors and Toba Amerindians from Rosario were typed for HNA-1a, HNA-1b and HNA-1c using polymerase chain reaction with sequence-specific primers. For the Argentinean blood donors, the HNA-1a and HNA-1b gene frequencies were 0.44 and 0.56 and for the Amerindians Toba were 0.77 and 0.23, respectively. The HNA-1c antigen is present in 4.7% (gene frequency ¼ 0.023) of the blood donors but in none of the Amerindian individuals. The present data showed that the HNA-1 allele frequencies in the major population and the Toba Amerindians from Rosario are similar to those described in European and others distant Amerindians populations, respectively. In our study, we report the genotype and gene frequency of the neutrophil-specific antigens belonging to the HNA-1 system in the major population and in an endogamous Amerindian group from Rosario, Argentina. Human neutrophil antigens (HNA) are polymorphic structures located on several glycoproteins in the neutrophil membrane. The neutrophil-specific antigens, HNA-1a (NA1), HNA-1b (NA2) and HNA-1c (SH), are well-recognized allotypic forms of FcgRIIIb and the most frequent target of neutrophil alloantibodies. Alloimmunization against these polymorphisms can result in neonatal immune neutropenia and transfusion-related acute lung injury, whereas autoim- munization against FcgRIIIb is frequently seen in autoim- mune neutropenia. HNA serologic typing (immunophenotyping) has been progressively replaced by genotyping methods for those antigens where the molecular structure is known. Frequencies of these antigens have previously been characterized in a small number of Caucasian and Asian populations and, although incomplete, the data show significant differences between populations. We were interested in the characterization of the Argentinean general population because of known differ- ences in the HNA-1 alleles frequencies between the migratory component from Europe, particularly from Italy (1) and Spain (2), and the indigenous component (3, 4). Rosario, the largest city of the province of Santa Fe, is located in the eastern region of central Argentina and its suburbs and neighboring towns comprise the third largest population in the country. In recent years, the migratory influx from others provinces has significantly increased, particularly from the north of the country. Among them, we found the highly endogamous Amerindian Toba group. The aim of this study was to determine the gene frequencies of the neutrophil-specific antigens belonging to the HNA-1 system in the major population and Toba Amerindians from Rosario, Argentina. We genotyped 192 unrelated healthy Argentinean adults recruited from blood donors (149 individuals) and hospital staff (43 individuals) of the Italian Hospital Garibaldi and 26 Toba Amerindians from Rosario. All participating individuals were born in Argentina and gave informed ª 2008 The Authors Journal compilation ª 2008 Blackwell Munksgaard  Tissue Antigens 71, 475–477 475