title: Direct molecular profiling of minicircle signatures and lineages of Trypanosoma cruzi bloodstream populations causing congenital Chagas disease.
abstract: Congenital transmission of Trypanosoma cruzi may occur in some or all the gestations from a T. cruzi-infected mother. Variable rates of congenital transmission have been reported in different geographical areas where different parasitic strains predominate, suggesting that parasitic genotypes might play a role in the risk of congenital transmission. Moreover, in cases of transmission it is unknown if the whole maternal T. cruzi population or certain clones are preferentially transmitted by the transplacental route. In this study, bloodstream T. cruzi lineages were identified in blood samples from congenitally infected children, transmitting and non-transmitting mothers and unrelated Chagas disease patients, using improved PCR strategies targeted to nuclear genomic markers. T. cruzi IId was the prevalent genotype among 36/38 PCR-positive congenitally infected infants, 5/5 mothers who transmitted congenital Chagas disease, 12/13 mothers who delivered non-infected children and 28/34 unrelated Chagas disease patients, all coming from endemic localities of Argentina and Bolivia. These figures indicate no association between a particular genotype and vertical transmission. Furthermore, minicircle signatures from the maternal and infants' bloodstream trypanosomes were profiled by restriction fragment length polymorphism of the 330-bp PCR-amplified variable regions in seven cases of mothers and congenitally infected infants. Minicircle signatures were nearly identical between each mother and her infant/s and unique to each mother-infant/s case, a feature that was also observed in twin deliveries. Moreover, allelic size polymorphism analysis of microsatellite loci from populations transmitted to twins showed that all clones from the maternal polyclonal population were equally infective to both siblings.
authors.affiliation: Laboratorio de Biología Molecular de la Enfermedad de Chagas (LaBMECh), Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI-CONICET), Buenos Aires, Argentina.
authors.forename: Juan M
authors.initials: JM
authors.lastname: Burgos
authors.forename: Jaime
authors.initials: J
authors.lastname: Altcheh
authors.forename: Margarita
authors.initials: M
authors.lastname: Bisio
authors.forename: Tomas
authors.initials: T
authors.lastname: Duffy
authors.forename: Helder M S
authors.initials: HM
authors.lastname: Valadares
authors.forename: María Elena
authors.initials: ME
authors.lastname: Seidenstein
authors.forename: Romina
authors.initials: R
authors.lastname: Piccinali
authors.forename: Jorge M
authors.initials: JM
authors.lastname: Freitas
authors.forename: Mariano J
authors.initials: MJ
authors.lastname: Levin
authors.forename: Liliana
authors.initials: L
authors.lastname: Macchi
authors.forename: Andrea M
authors.initials: AM
authors.lastname: Macedo
authors.forename: Hector
authors.initials: H
authors.lastname: Freilij
authors.forename: Alejandro G
authors.initials: AG
authors.lastname: Schijman
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D001118:Argentina / Q000453:epidemiology; D001838:Bolivia / Q000453:epidemiology; D014355:Chagas Disease / Q000151:congenital* / Q000453:epidemiology / Q000635:transmission; D002648:Child; D002675:Child, Preschool; D016054:DNA, Protozoan / Q000235:genetics*; D004198:Disease Susceptibility; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical / Q000706:statistics & numerical data*; D008297:Male; D009035:Mothers; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D015597:Pregnancy Complications, Parasitic / Q000235:genetics*; D012307:Risk Factors; D014349:Trypanosoma cruzi / Q000235:genetics*
chemical_list: D016054:DNA, Protozoan