Vol 9, No 3 (2020)
Research paper
Published online: 2020-06-01

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Molecular genetic analysis of leucine tRNA in relevance to type 2 diabetes mellitus

Niaz Muhammad Khan1, Hayat Ullah1, Abdur Raziq1, Adnan Ali Khan2, Muhammad Waseem Khan3
Clin Diabetol 2020;9(3):167-173.


Background. Several point mutations in the mitochondrial DNA cause maternally inherited metabolic disorders. The most common type of mutation A3243G in the gene of transfer RNA leucine (tRNALeu(UUR)) is thought to be responsible for the prevalence of type 2 diabetes mellitus. This study was designed to analyze the tRNALeu(UUR) gene of mtDNA of the diabetic individuals with familial history of diabetes to identify the point mutations A3243G.

Material and methods. Saliva samples were preferred as a source of DNA to minimize the risk of infection. DNA was successfully extracted from their saliva. Samples of high-quality DNA was amplified with PCR and sequenced in Macrogen Inc. Korea.

Results. The m.3243A>G mutation in mitochondrial tRNALeu(UUR) gene was not observed.

Conclusion. The result shows that the m.3243A>G mutation in mitochondrial tRNALeu(UUR) gene is not frequent cause of type 2 and some other factors may be possible i.e. genetic, behavioral or environmental. It is recommended that the sample size for diabetic individuals need to be increased for a future study and screened for the mitochondrial as well as other mutations of nuclear origin.

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