Instability at Short Tandem Repeats in Lymphoblastoid Cell Lines

OBJECTIVES: Epstein Barr virus (EBV)-transformed lymphoblastoid cell lines (LCLs) are a useful biological resource, however, genomic variations can happen during the generation and immortalization processes of LCLs. The purpose of this study was to identify genomic variations in LCL DNA compared with matched blood DNA using short tandem repeats (STRs) analysis. METHODS: We analyzed 15 STRs with blood DNA and their matched LCL DNA samples from 6645 unrelated healthy individuals. RESULTS: Mutations (such as repeat variations and triallelic patterns) of 15 STR loci were detected in 612 LCL DNAs (9.2% of total) without mutations in their matched blood DNA. The repeat variations of 15 STRs were detected in 526 LCL DNAs (mutation rate = 0.0792) and triallelic patterns were identified in 123 (mutation rate = 0.0185). Among 15 STRs, the most common repeat variations (n = 214, mutation rate = 0.0322) and triallelic patterns (n = 17, mutation rate = 0.0026) were found at FGA locus. CONCLUSION: Our study shows that mutations in STRs can occur during generation and immortalization of LCLs.