OBJECTIVE To investigate the relationship between genetic polymorphim of X-ray repair cross complementing gene 1(XRCC1) and EBV infection in NPC cell.METHODS NPC CNE cell strain was divided into different groups depending on its XRCC1 genetic polymorphism,and EBV was transferred into different groups.Characteristics of cells and XRCC1 protein were detected among different groups before and after EBV transferring.RESULTS There was no difference in cell characteristics and XRCC1 protein level among different genotypes in NPC CNE cells strain.After EBV transferring,there was an increasing in cell malignancy in NPC cells,including control group,wild type group,and 194,280,399 mutant genotype groups,and the differences were statistically significant(P>0.05).There was no difference in XRCC1 protein level before and after EBV transferring.Compared with other groups,the increasing in cell malignancy was less in the 194 mutant genotype group before and after EBV transferring,especially in cell migration and proliferation.There were no difference in the increasing of cell malignancy and XRCC1 protein level among control group,wild type and 280,399 mutant genotypes of NPC CNE cells before and after EBV transferring.CONCLUSION The results suggest that EBV transferring can raise the carcinogenicity of NPC cell.After EBV transferring,the 194 mutant genotype is associated with a reduced carcinogenicity of NPC cells compared with other genotypes.

OBJECTIVE Exploring the TNC gene mutations in a family with hereditary hearing loss and their relationship with clinical phenotypes.METHODS Draw the family pedigree chart,analyze the inheritance pattern,and assess the clinical phenotypes of family members using audiologic,imaging,and vestibular function tests.Perform whole exome sequencing on six members of the family to identify candidate mutations potentially related to hearing loss,and validate the distribution of these candidate mutations within the family and in normal controls using Sanger sequencing.RESULTS A heterozygous mutation c.5110G>T(p.Ala1704Ser)in exon 17 of the TNC gene on chromosome 9 was identified in the family.This mutation is associated with hereditary hearing loss.Carriers of this gene mutation all presented with normal hearing at birth and hearing decline during childhood;imaging examinations showed no abnormalities in the middle ear or inner ear structures.CONCLUSION This study reports for the first time the association between the heterozygous mutation c.5110G>T(p.Ala1704Ser)in the TNC gene and hereditary hearing loss,providing new evidence for molecular diagnosis and genetic counseling in cases of hereditary hearing loss.