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P35: Study on the loss of heterozygosity of microsatellite allele in thymic epithelial tumors

ABSTRACT: Background To study the relationship between loss of heterozygosity (LOH) on human leukocyte antigen (HLA) locus and the pathogenesy and clinicopathological features of thymic epithelial tumor. Methods Choose 36 thymic epithelial tumor patients in Tianjin Medical University General Hospital. Amplify five microsatellite loci (D6S1666, D6S265, D6S273, DS6276 and D6S291) of 36 thymic epithelial tumors and paired normal tissues by PCR. Detect the condition of base loss using DNA sequencing technique. Analyze the frequency of microsatellite LOH. Results A total of 83.6% of the thymic epithelial tumors showed LOH on at least one locus; the rate of LOH which was detected at loci of D6S1666, D6S265, D6S273, D6S276 and D6S291 was 44.4%, 16.7%, 30.5%, 38.9% and 36.1% separately. There is no significant association between LOH with thymic epithelial tumor with or without myasthenia gravis (MG) and the benign or malignant thymic epithelial tumor. Conclusions D6S1666, D6S265, D6S273, DS6S276 and D6S29 are sensitive loci for studying microsatellite DNA in thymic epithelial tumor. LOH on HLA complex play a certain role in occurrence and development of thymic epithelial tumor, the most likely involving gene is HLA-DQA1, but the relationship between LOH and clinicopathological features of thymic epithelial tumor needs to expand the sample size for further study.

SUBMITTER: Zhang P

PROVIDER: S-EPMC4700324 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature

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