Detection of Mitochondrial A12308G Mutation in tRNALeu(CUN) Gene and its Relation with Colorectal Cancer Risk

A mitochondria have important role in oxidative phosphorylation, each cell have many copies of mitochondria. Mitochondrial DNA (mtDNA) in human is a 16.569 kb circular double stranded molecule able for replication, transcription and translation. MtDNA represent the unique genetic material outside the nucleus in eukaryotic cells. This study was conduct on 36 Iraqi patients with colorectal disease to analyze the genetic mutation in A12308G of mtDNA tRNALeu (CUN) gene for its etiology role in inflammation bowel and colorectal tumorgenesis using conventional polymerase chain reaction (PCR) and sequencing analysis. The results referred to that total frequency of the A12308G transition was showed 6 variations out of 18 patients (33.3 %) in colorectal patients but these differences were not statistically significant, similar distribution for the frequency of the G12372A transition mutations was found in combination with A12308G polymorphism patients. Total of 7 out 18 patients (38.8 %) were presence as insertion (ins) base between (12413-12414). Statistically significant results with high rate of deletion 11924A base was showed in 10 out of 18 samples (55.5 %), coexisted of A12308G with G12372A mutations in addition to that in combination of A12410 C with T12414A may have synergistic effect in functions and associated with risk factor in colorectal cancer, finally large deletion site in (12380. . .12425) and (12383. . .12425) positions were described only in two tumor patients may be effect the colorectal cancer progression. In conclusions The mtDNA A12308G tRNALeu (CUN) gene variant may be dont have risk factor for malignant process of colorectal. Identify the predictive role of the mt tRNALeu (CUN) gene variations may be use as genetic biomarker in colorectal cancer, high rate of novel mutations that were found may serve as supporting factor in colorectal etiology and tumorgensis.