Short communication Identifying four Trypanosoma cruzi I isolate haplotypes from different geographic regions in Colombia § Claudia Herrera a, * , M. Dolores Bargues b , Anabella Fajardo a , Marleny Montilla c , Omar Triana d , Gustavo Adolfo Vallejo e , Felipe Guhl a, ** a Centro de Investigaciones en Microbiologı ´a y Parasitologı ´a Tropical (CIMPAT), Universidad de los Andes, Bogota ´, Colombia b Departamento de Parasitologı ´a, Facultad de Farmacia, Universidad de Valencia, Spain c Grupo de Parasitologı ´a, Instituto Nacional de Salud, Bogota ´, Colombia d Grupo de Chagas, Universidad de Antioquia, Medellı ´n, Colombia e Laboratorio de Investigaciones en Parasitologı ´a Tropical, Facultad de Ciencias, Universidad del Tolima, Ibague ´, Colombia Received 15 December 2006; accepted 19 December 2006 Available online 28 December 2006 Abstract Trypanosoma cruzi has been classified into the groups T. cruzi I and T. cruzi II. The latter is subdivided into five smaller lineages based on multilocus enzyme electrophoresis and random amplified polymorphic DNA, designated as IIa-IIe, which shows correspondence with rRNA/mini- exon lineages. Twelve previously characterised T. cruzi isolates from different hosts, including humans, Didelphis marsupialis, and triatomines were analysed to establish genetic variability in T. cruzi group T. cruzi I isolates from different geographical regions of Colombia. DNA samples were sequenced based on the mini-exon gene intergenic region. Sequences were analysed using Clustal W, Staden 1.5 and MEGA3 software, and using reported sequences from the GenBank as reference. The genetic distances were analysed using Kimura’s two-parameter model. The isolates’ joint alignment was of 350 bp, and the calculated nucleotide divergence was of 17.5%. The differences consisted of 23 transitions (7.2%), 14 transversions (4.4%) and 19 insertion–deletions (5.9%). The Colombian T cruzi I isolates revealed sufficient genetic variability for us to propose the existence of four haplotypes identified through single nucleotide polymorphism (SNP) and insertion/deletion found in the mini-exon gene’s non-transcribed spacer intergenic region. # 2007 Published by Elsevier B.V. Keywords: Trypanosoma cruzi I; Chagas disease; PCR; Genetic variation; Haplotypes; Mini-exon gene 1. Introduction Chagas disease is a very complex zoonosis which stretches throughout the whole of South-America, Central-America and Mexico, constituting a serious public health problem for many countries in this region. People infected with Trypanosoma cruzi can manifest diverse clinical symptoms (heart, gastro- intestinal or neurological lesions) depending on the endemic area (Devera et al., 2003; M. Miles et al., 2003; M.A. Miles et al., 2003; Guhl et al., 2004). Eighteen million people are currently infected in Latin America, and 25% of the remaining population is at the risk of contracting the disease; thus, highlighting the need to extend strategies for fighting it (WHO, 2002). As a result of their particular method of clonal propagation, T. cruzi strains have been described as showing great heterogeneity in their phenotype and genotype (Tibayrenc et al., 1986; Tibayrenc and Ayala, 2002). Despite their high genetic variability, T. cruzi isolates could be classified into two groups, T. cruzi I and T. cruzi II, based on mini-exon (ME) sequences, or spliced leader (SL) RNA gene promoter sequences (Nun ˜es et al., 1997; Souto et al., 1996; Briones et al., 1999). Five subgroups have been identified within the T. cruzi II group, designated T. cruzi IIa-e. No clear subdivision has, however, been found within the T. cruzi I www.elsevier.com/locate/meegid Infection, Genetics and Evolution 7 (2007) 535–539 § Note: Nucleotide sequence data reported in this paper are available in the GenBank TM , EMBL and DDBJ databases under the accession number AM259467–AM259480. * Corresponding author at: A.A. 4976.Carrera 1, No. 18-A-10, Bogota ´, Colombia. Tel.: +57 1 332 45 40; fax: +57 1 332 45 40. ** Co-Corresponding author. E-mail addresses: cherrera@uniandes.edu.co (C. Herrera), fguhl@uniandes.edu.co (F. Guhl). 1567-1348/$ – see front matter # 2007 Published by Elsevier B.V. doi:10.1016/j.meegid.2006.12.003