Factor V Leiden mutation in one family of Chinese origin

Objective To investigate the factor V Leiden mutation associated with activ ated protein C resistance (APCR) in Chinese. Methods Thirty "normal" individuals and twenty patients with thrombotic dis ease from Chinese Han Nationality were studied with APTT +/- APC, PCR follo wed by MnLI restriction enzyme analysis, PCR based direct sequence-specific primers (PCR-SSP) and DNA sequence analysis. Results In one healthy control, the activated protein C (APC) sensitivity r atio (SR) was found to be significantly lower (0.8) than that in other norm al control (> 2.0). This individual was identified to be heterozygous for F V Leiden mutaiton (Arg506-Gln). His grand-uncle, father, brother and son we re also identified to be heterozygous for FV Leiden. The APC resistance was found in 3 other cases of thrombotice diseases, but with no FV Leiden muta tion. Conclusion This is the first four generations family case of FV Leiden muta tion associated with APCR reported within Chinese ethnic population. It is note-worthy that more FV Leiden or whether other gene defects may be associ ated with APC resistance and acquired APCR causing thrombosis in Chinese po pulation.