22Q11 DELETION AND POLYMORPHISMS ASSOCIATED WITH COAGULOPATHY IN TETRALOGY OF FALLOT PATIENT: CASE REPORT

Background: In recent years, there has been a notable effort to investigate the genetic mechanisms contributing to the development of congenital heart diseases (CHD) and their various forms of presentation. Aim: This study aims to examine and characterize the presence of multiple genetic alterations in Tetralogy of Fallot (TOF) patients using the MLPA and qPCR techniques. Materials and methods: Our study followed four patients with TOF diagnosis admitted at mar/2016. Molecular, clinical evaluation and biochemical were performed in Fundação Hospital do Coração Francisca Mendes (FHCFM). Analysis of SNVs was performed by qPCR, using TaqMan® system, and analyzed by QuantStudio™ 6 Flex Real-Time PCR System (Applied Biosystems) platform to the gene TGFB, AMPD, IL-6, Klotho; BCL11A; HMIP; OR51B5; FVL; SERPINE1; FII; MYH9; THBS1; NOS3; SOD2 and MTHFR. The Multiplex ligation- dependent probe amplification (MLPA) using the MLPA P-311 CHD kit (MRC-Holland) at Laboratório de Análise Especializada em Biologia Molecular (LAEBM) of the Universidade Federal do Amazonas (UFAM). Results: The female newborn (8 weeks), born via the C/S section after 38 gestational weeks, with cyanotic episodes following the TOF diagnose. The molecular analysis showed the presence of six SNV in heterozygous mutations: HMIP (rs11759553), IL6 (rs2069845, rs1524107, rs2069849) and THBS1 (rs1478604) and homozygous to AMPD1 (rs17602729). The MLPA analysis demonstrated a deletion in 22q11.2 chromosomal region with decreased ratio of three probes targeting the CDC45-1, GP1BB-2, and DGCR8-14 exons, respectively. Discussion: In this study we used SNV qPCR probes combined to MLPA to characterize and differentiate the present genotypes in TOF. It is described that the found genotype affects early operative outcomes in TOF resulting in longer duration of intensive care, although no difference was found in the clinical and biochemical following postoperative intervention. Our results corroborate that 22q11.2 deletion syndrome was not associated with adverse perioperative outcomes. The presence of SNV as a risk factor to CHD is being strongly investigated, addressing several genes which may impair hemostatic and immunological functions and expression at the heart formation period. Conclusion: We characterized the presence of six SNV in important genes associated with increased oxidative stress and coagulopathies, in addition to the chromosomal alteration 22q11.2 in a newborn with no significant association with adverse postoperative periods.