polymorphism in Non-coding Region of Human Mitochondrial DNA in Persian TypeII Patient

Population genetic inference would benefit from a better understanding of the variation in the mtDNA coding region, but, thus far, complete mtDNA sequences have been rare. We determined the nucleotide sequence in the none-coding region of mtDNA from Persian patients through direct sequencing of the Displacement(D) loop. The D-loop region is a hot spot for mtDNA alterations and it contains two hypervariable regions. The sequence in the first Hyper Variable Segment (HVS-I) of the control region has been used as a source of evolutionary information in most phylogenetic analyses of mtDNA. In order to find for any maternally inherited genetic background of diabetes type II, the polymorphic sites and also to screen potential variations in the D-loop, the complete non-coding region of mitochondrial DNA from 7 Azari diabetic patients (clinically diagnosed) and 23 normal controls (people with no history or family record of diabetes) of the same origin were sequenced. The sequences were aligned upon the Cambridge Reference Sequence (CRS) and any incompatibilities were recorded as single base substitution (SBS), numerical changes in Homo-Polymeric C Tract (PCT), insertions or deletions. PCT changes were present in 52% of normal controls compared to 71% diabetic patients. We found that polymorphism C150T existed in 42.8% of diabetic patients versus 28.6% in normal controls. Also variation in T16189C was found in 14.2% of diabetic patients compared to 28.6% in normal samples. mtDNA mutations within the D-loop control region is frequently reported recurrence in diabetes type II and may be an indicator of mtDNA instability.

کلیدواژه ها:

Diabetes Type II ، mtDNA ، D-loop