Genetic variation of the gene coding for microRNA-204 (miR-204) is a risk factor in acute myeloid leukaemia

Background: MicroRNAs (miRNAs or miRs) are small molecules known to be involved in post-transcriptional gene expression. Many of them have been shown to influence risk for various diseases. Recent studies suggest that lower expression of miR-204, a gene coding for miRNA-204, is correlated with shorter survival in patients with acute myeloid leukaemia (AML). This observation prompted us to analyse the effect of two polymorphisms of the miR-204 gene, one in the upstream flanking region (rs718447 A > G) and the other inside the gene itself (rs112062096 A > G), both also in intron 3 of the TRPM3 gene. Methods: The study was conducted on DNA samples isolated from AML patients (n = 95) and healthy individuals (n = 148), who were genotyped using the Light SNiP assays. Results: The miR-204 rs718447 GG homozygosity was found to constitute a risk factor associated with susceptibility to AML (73/95 vs 92/148, AML patients vs healthy controls, OR = 2.020, p = 0.017). Additionally, this genotype was more frequent in patients with subtypes M0-M1 in the French-American-British (FAB) classification as compared to patients with subtypes M2-M7 (23/25 vs 39/57, p = 0.026). We also found that presence of allele A was linked to longer survival of AML patients. Conclusions: Our results show that polymorphism in miR-204 flanking region may constitute a risk and prognostic factor in AML.