Study on the Sensitive Method for Screening the Markers of Children Acute Lymphatic Leukemia

Objective: T-cell receptor(TCR) and immunoglobulin heavy chain(IgH) gene rearrangements are specific markers of minimal residual disease levels that are strongly correlated with the risk of relapse of childhood acute lymphoblastic leukemia(ALL).However, conventional polymerase chain reaction(PCR) methods to detect IgH/TCR gene rearrangements are time-consuming, labor-intensive and less sensitive. To explore a more efficient and sensitive method. Methods: We used multiplex PCR to detect these markers in peripheral blood samples of 26 children with ALL diagnosed in 2 years in Harbin, China. We used Gene Scan method in detection of IgH(FRI, FRII and FRIII)/TCR(TCR β and TCR γ) gene rearrangements and performed fragment analysis of PCR products by capillary electrophoresis. Results: The result showed that positive rate for IgH/TCR gene rearrangements and for IgH gene rearrangements was 92.3%and 75%, respectively. Among the 26 cases, four patients who suffered from relapsing showed positive gene rearrangements of all the three fragments of IgH(FRI, FRII and FRIII). Further analysis revealed a linear correlation between relapsing and IgH gene rearrangements. Conclusion: Our experiment and clinical applications indicate that Gene Scan method is reliable and applicable for detection of IgH/TCR gene rearrangements. Thus, our method can be used in diagnosis and follow-up in Childhood ALL.