RESUMEN
ETV6::RUNX1 is a genetic rearrangement of good prognosis in children with acute lymphoblastic leukemia (ALL). In Mexico, its prevalence is low in comparison with Caucasian populations. We developed a novel TaqMan one-step RT-qPCR approach to assess the prevalence of four genetic rearrangements in a cohort of Hispanic children with ALL from Mexico City. The prevalence of common fusion gene transcripts was as follows: TCF3::PBX1 7.7%; BCR::ABL1p 190 3.3%; and KMT2A::AFF1 2.8%, and ETV6::RUNX1was observed with low prevalence (10.5%) in comparison to that reported for developed countries. This is consistent with previous findings on Mexican children with ALL and similar to those reported on children from Hispanic populations. The confirmation of a low prevalence of ETV6::RUNX1 in children of a Hispanic origin represents an advancement in the description of genetic factors of ALL in these populations.
RESUMEN
Lambda bacteriophage development is impaired in Escherichia coli cells defective for peptidyl (pep)-tRNA hydrolase (Pth). Single-base-pair mutations (bar(-)) that affect translatable two-codon open reading frames named bar minigenes (barI or barII) in the lambda phage genome promote the development of this phage in Pth-defective cells (rap cells). When the barI minigene is cloned and overexpressed from a plasmid, it inhibits protein synthesis and cell growth in rap cells by sequestering tRNA(2)(Ile) as pep-tRNA(2)(Ile). Either tRNA(2)(Ile) or Pth may reverse these effects. In this paper we present evidence that both barI and barII minigenes are translatable elements that sequester tRNA(2)(Ile) as pep-tRNA(2)(Ile). In addition, overexpression of the barI minigene impairs the development even of bar(-) phages in rap cells. Interestingly, tRNA or Pth may reestablish lambda phage development. These results suggest that lambda bar minigenes are expressed and tRNA(2)(Ile) is sequestered as pep-tRNA(2)(Ile) during lambda phage development.
