Laboratory of Population Genetics, Department of Biochemistry and Molecular Biology, University of Dhaka, Dhaka, Bangladesh.
Translational Systems Biology Laboratory, Department of Biochemistry and Molecular Biology, University of Dhaka, Dhaka, Bangladesh.
PLoS Negl Trop Dis. 2022 Jun 30;16(6):e0010537. doi: 10.1371/journal.pntd.0010537. eCollection 2022 Jun.
The current study elucidated an association between gene variants and thrombocytopenia through the investigation of the exonic polymorphic landscape of hematopoietic transcription factor-GATA1 gene in dengue patients. A total of 115 unrelated dengue patients with dengue fever (DF) (N = 91) and dengue hemorrhagic fever (DHF) (N = 24) were included in the study. All dengue patients were confirmed through detection of NS1 antigen, IgM, and IgG antibodies against the dengue virus. Polymerase chain reaction using specific primers amplified the exonic regions of GATA1 while Sanger sequencing and chromatogram analyses facilitated the identification of variants. Variants G>A (at chX: 48792009) and C>A (at chX: 4879118) had higher frequency out of 13 variants identified (3 annotated and 10 newly recognized). Patients carrying either nonsynonymous or synonymous variants had significantly lower mean values of platelets compared to those harboring the reference nucleotides (NC_000023.11). Further analyses revealed that the change in amino acid residue leads to the altered three-dimensional structure followed by interaction with neighboring residues. Increased stability of the protein due to substitution of serine by asparagine (S129N at chX: 48792009) may cause increased rigidity followed by reduced structural flexibility which may ultimately disturb the dimerization (an important prerequisite for GATA1 to perform its biological activity) process of the GATA1 protein. This, in turn, may affect the function of GATA1 followed by impaired production of mature platelets which may be reflected by the lower platelet counts in individuals with such variation. In summary, we have identified new variants within the GATA1 gene which were found to be clinically relevant to the outcome of dengue patients and thus, have the potential as candidate biomarkers for the determination of severity and prognosis of thrombocytopenia caused by dengue virus. However, further validation of this study in a large number of dengue patients is warranted. Trial Registration: number SLCTR/2019/037.
本研究通过调查造血转录因子 GATA1 基因的外显子多态性景观，阐明了基因变异与血小板减少症之间的关联。共纳入 115 例无亲缘关系的登革热患者，其中登革热（DF）患者 91 例，登革出血热（DHF）患者 24 例。所有登革热患者均通过检测 NS1 抗原、登革病毒 IgM 和 IgG 抗体进行确认。特异性引物的聚合酶链反应扩增了 GATA1 的外显子区域，而 Sanger 测序和色谱分析有助于识别变体。在鉴定的 13 个变体中，变体 G>A（在 chX:48792009）和 C>A（在 chX:4879118）的频率更高（3 个注释变体和 10 个新识别变体）。与携带参考核苷酸（NC_000023.11）的患者相比，携带非同义或同义变体的患者血小板的平均值明显较低。进一步的分析表明，氨基酸残基的变化导致三维结构的改变，随后与相邻残基相互作用。由于丝氨酸被天冬酰胺取代（在 chX:48792009 处的 S129N）导致蛋白质稳定性增加，随后结构灵活性降低，这可能最终干扰 GATA1 蛋白的二聚化（GATA1 发挥其生物学活性的重要前提）过程。反过来，这可能会影响 GATA1 的功能，导致成熟血小板的产生受损，这可能反映在具有这种变异的个体中血小板计数较低。总之，我们在 GATA1 基因中发现了新的变体，这些变体与登革热患者的结局相关，因此具有作为确定登革病毒引起的血小板减少症严重程度和预后的候选生物标志物的潜力。然而，需要在大量登革热患者中进一步验证这项研究。试验注册：SLCTR/2019/037 号。
