Minimum Free Energy Based Evaluation of mRNAs Secondary Structures Constructed by 18 Clinically Significant Exonic Single Nucleotide Polymorphisms (SNPs) and Haplotypes of 5 Missense SNPs of RB1 Gene

Abstract

Clinically significant 18 Single Nucleotide Polymorphisms (SNPs) from exon regions of Retinoblastoma gene (RB1) were analyzed to find out the structural variations in mRNAs. Online bioinformatic tools i.e., Vienna RNA, RNAfold were used for secondary structure analysis of mRNAs. Predicted minimum Free Energy Change (MFE) was calculated for mRNAs structures. It has been observed that the average of predicted MFE value from 13 nonsense mutations was higher (0.76 kcal/mol) in comparison to 5 missense mutations. Presumably, 13 nonsense mutations are responsible for Nonsense Mediated mRNA Decay (NMD), therefore, excluded from haplotype analysis. From the statistical analysis all the thermodynamic data obtained from four SNP haplotypes are significant (p≤0.05), followed by three-SNP haplotype data except Ensemble diversity (p≤0.10). Interestingly, MEF of Centroid Secondary Structure is highly significant (p≤0.01) in all the cases (Two-SNP haplotypes, Three-SNP haplotypes and Four-SNP haplotypes).