Recent Advances in Understanding the Role of Genomic and Epigenomic Factors in Noncommunicable Diseases
The NGS based whole genome and exome sequencing endeavors have identified a plethora of mutations in the coding regions of the human genome that are held responsible as the causative factors for various human noncommunicable diseases including cancer. These mutations encompass various nonsynonymous nucleotide substitutions causing missense, nonsense, and frameshift changes in the protein-coding genes. For these types of mutations it is easier to establish a causal link between these mutations and disease phenotypes as they tend to change the amino acids in the proteins resulting in their loss-of-function (of tumor suppressor genes) or gain-of-function (of oncogenes) which might be directly responsible for the disease such as cancer. Apart from these disease-causing mutations, vast majority (more than 80%) of single-nucleotide polymorphisms were distributed throughout the human genome, mostly in the noncoding regions such as introns and intergenic regions. Large body of evidence suggested that variants in the noncoding regions can be considered as genetic predisposition to many noncommunicable diseases including cancer.