ABSTRACT
<p><b>OBJECTIVES</b>To study the relationship between quasispecies of hepatitis B virus and the clinical manifestations of their infection, and to find the answer of why different quasispecies of HBV with the same genotype can induce different clinical situations.</p><p><b>METHODS</b>Sixty serum samples, in all of which HBVs of genotype B exist, taken from 32 chronic asymptomatic carriers and 28 severe chronic hepatitis patients, were collected to detect quasispecies of HBV DNA by melt curve approach. Then the relationship between quasispecies of HBV of the same genotype and the clinical situation of their infection was studied by comparing the wave crests of the two sample groups.</p><p><b>RESULTS</b>The data of the 60 serum samples of HBV of genotype B detected by melt curve showed that HBV DNA in severe chronic hepatitis patients had more wave crests than that in chronic asymptomatic carriers (P < 0.05), suggesting that HBV in severe chronic hepatitis patients had more quasispecies than in the chronic asymptomatic carriers.</p><p><b>CONCLUSION</b>The numbers of quasispecies of HBV correlate with the clinical situations of their infection. In the patients infected by HBV of the same genotype, those who have more HBV quasispecies would have more severe clinical manifestations.</p>