MGB probe assay for rapid detection of mtDNA11778 mutation in the Chinese LHON patients by real-time PCR.

OBJECTIVE: Leber's hereditary optic neuropathy (LHON) is a maternally inherited degeneration of the optic nerve caused by point mutations of mitochondrial DNA (mtDNA). Many unsolved questions regarding the penetrance and pathophysiological mechanism of LHON demand efficient and reliable mutation testing. This study aims to develop a minor groove binder (MGB) probe assay for rapid detection of mtDNA11778 mutation and heteroplasmy in Chinese LHON patients by real-time polymerase chain reaction (PCR). METHODS: Forty-eight patients suspected of having LHON and their maternal relatives underwent a molecular genetic evaluation, with 20 normal individuals as a control group at the same time. A real-time PCR involving two MGB probes was used to detect the mtDNA11778 mutation and heteroplasmy. A linear standard curve was obtained by pUCmLHONG and pUCmLHONA clones. RESULTS: All 48 LHON patients and their maternal relatives were positive for mtDNA11778 mutation in our assay, 27 heteroplasmic and 21 homoplasmic. Eighteen cases did not show an occurrence of the disease, while 9 developed the disease among the 27 heteroplasmic mutation cases. Eleven did not show an occurrence of the disease, while 10 cases developed the disease among 21 homoplasmic mutation cases. There was a significant difference in the incidence between the heteroplasmic and the homoplasmic mutation types. The time needed for running a real-time PCR assay was only 80 min. CONCLUSION: This real-time PCR assay is a rapid, reliable method for mtDNA mutation detection as well as heteroplasmy quantification. Detecting this ratio is very important for predicting phenotypic expression of unaffected carriers.

Expression of A, G and B melanoma antigen genes in human hepatocellular carcinoma.

OBJECTIVE: To observe the expression of the A melanoma antigen (MAGE), G melanoma antigen (GAGE) and B melanoma antigen (BAGE) genes in human hepatocellular carcinoma cell lines. METHODS: The MAGE-1,MAGE-3,GAGE1-8,GAGE1-2 and BAGE mRNA lever in hepatocellular carcinoma cell lines SMMC-7721, QQY-7701, BEL-7402 were studied by reverse transcription polymerase chain reaction and were compared with biopsied liver tissues. RESULTS: MAGE-1 and BAGE mRNA were expressed in SMMC-7721, MAGE-3 and BAGE in QGY-7701, MAGE-1 and GAGE1-2 in BEL-7402. None of these genes was expressed in biopsied liver tissues. CONCLUSIONS: MAGE-1, MAGE-3, GAGE1-8, GAGE1-2 and BAGE were expressed in hepatocellular carcinoma cell lines, respectively. These tumor-specific antigens can be used as molecular markers and possible targets of immunotherapy for patients with hepatocellular carcinoma.