EVALUATION OF DNA METHYLTRANSFERASE 1 IN SICKLE CELL PATIENTS

ABSTRACT

Previous studies suggested that management therapy ranging from hydroxyurea medication to innovative gene-editing techniques may not only improve clinical symptoms but also influence the epigenetic landscape of those affected. Therefore, the aim of this study was to determine the effect of hydroxyurea therapy on DNA methyl transferase 1 activity in sickle cell subjects. One hundred subjects from the university of Benin teaching hospital were recruited for this study. Sixty (60) were sickle cell subjects while 40 were homozygous AA control. Enzyme-linked Immunosorbent Assay (ELISA) and Sysmex autoanalyzer were used to determine DNMT1 and full blood count parameters respectively. Data collected was analysed using GraphPad prism 8.02 statistical software. The results showed that DNA methyltransferase 1 activity in sickle cell subjects (2.347±0.2472) was significantly low (p<0.0001) when compared to control (10.39±2.229). SCD subjects on hydroxyurea (2.342±0.8018) had a significantly lower (p<0.0001) DNA methyltransferase 1 activity when compared to subjects on L-glutamine (7.567±0.9179). Those on L-glutamine also had a significantly higher (p<0.0001) DNA methyltransferase 1 activity when compared to Crizenlizumab (1.814±0.883), Voxelotor (2.757±1.054), folic acid (2.151±0.245) and pain medication (2.163±0.240). The haematological parameters showed that total white cell count was significantly higher (p=0.0305) in sickle cell subjects (11.53±1.126) when compared to controls (5.39±0.326). Packed cell volume (25.4±0.5601), haemoglobin concentration (8.468±0.1863), red blood cell count (3.462±0.1035) and MCHC (334.9±5.755) were all significantly lower (p<0.0001) in sickle cell subjects when compared to controls (PCV (38.3±0.4955); HB (12.83±0.1814); RBC (5.58±0.07424); MCHC (383.9±3.25)) respectively. The data collected showed that 25% of SCD subjects in this study had relatives who also had SCD while 75% of the SCD subjects had no relative with SCD. Most of the SCD subject had just one other sibling (16.67%) with SCD, 6.67% of SCD subjects had more than one sibling with SCD while 1.67% of the SCD subject’s fathers had SCD. Leg ulcer (81.67%) accounted for the common complication in sickle cell subjects recruited for this study, followed by acute chest syndrome (80%), vaso-occulusive crises (76.67%), osteomyelitis (23.33%), retinopathy (11.67%), priapism (10%) and nephropathy (6.67%). The frequency of complications also shows that most complication happened monthly (50%) while others occurred more than monthly (23.33%). 21.67% of the SCD were current in one form of crisis. In conclusion, DNA methyltransferase 1 was very low in sickle cell subjects which indicate aberrant epigenetic activity. Also, we found that DNMT1 activity was lower in patients receiving hydroxyurea therapy compared to those on L glutamine.