Table 3.
Molecular characterization of mt-tRNA mutations identified by PCR-Sanger sequencing
| Genes | Mutation | Number of nucleotide in tRNAs | Location | Homoplasmy/Heteroplasmy | CI (%) | 80 patients (%) | 50 controls (%) | Disease association |
|---|---|---|---|---|---|---|---|---|
| tRNALeu(UUR) | A3302G | 71 | Acceptor arm | Homoplasmy | 100 | 1 (1.25) | 0 | MELAS |
| C3275A | 44 | Extra loop | Homoplasmy | 86.6 | 2 (2.5) | 0 | LHON | |
| tRNAGln | T4363C | 38 | Anticodon stem | Homoplasmy | 73.3 | 4 (5) | 0 | Hypertension, Development delay |
| T4395C | 6 | Acceptor arm | Homoplasmy | 100 | 1 (1.25) | 0 | Hypertension | |
| tRNACys | G5821A | 6 | Acceptor arm | Homoplasmy | 66.6 | 3 (3.75) | 1 (2) | Deafness |
| tRNASer(UCN) | C7492T | 26 | Anticodon stem | Homoplasmy | 100 | 1 (1.25) | 0 | PCOS-IR |
| tRNAAsp | A7543G | 29 | Anticodon stem | Homoplasmy | 73.3 | 1 (1.25) | 0 | MEPR |
| tRNALys | A8343G | 54 | T-loop | Homoplasmy | 86.6 | 2 (2.5) | 0 | PD risk factor |
| tRNAArg | T10454C | 55 | T-loop | Homoplasmy | 93.3 | 2 (2.5) | 0 | Deafness |
| tRNAGlu | A14693G | 54 | T-loop | Homoplasmy | 100 | 1 (1.25) | 0 | Deafness, Hypertension |
| tRNAMet | T4454C | 58 | T-loop | Homoplasmy | 60 | 0 | 2 (4) | Neutral polymorphism |
| tRNAThr | T15900C | 13 | D-arm | Homoplasmy | 46.6 | 0 | 1 (2) | Neutral polymorphism |
Abbreviations: MELAS: Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes; LHON: Leber’s hereditary optic neuropathy; MEPR: Myoclonic epilepsy and psychomotor regression; PD: Parkinson’s disease.