Abstract:OBJECTIVE: To study the relationship of methylation of inhibitor of DNA binding 4 (ID4) gene core promoter region with childhood T line, B line and T/B acute lymphocytic leukemia (ALL). METHODS: Methylation-specific polymerase chain reaction (MS-PCR) was used to detect the methylation status of ID4 promoter region in 18 children with newly-diagnosed ALL (2 cases of T-ALL, 13 cases of B-ALL and 3 cases of T/B-ALL). Thirty-four hospitalized children with non-tumor disease served as the control group. RESULTS: The complete methylation rate of ID4 gene promoter region (15/18, 83%) was significantly higher than the partial methylation rate (3/18, 17%) in the 18 ALL children (P<0.05). The complete methylation rate of ID4 gene promoter region in children with T-ALL, B-ALL and T/B-ALL (50%, 85% and 100% respectively) was significantly higher than that in the control group (18%; P<0.05). In contrast, the partial methylation rate and non-methylation rate in the three ALL groups were significantly lower than those in the control group (P<0.05). There were no statistically significant differences in the methylation patterns among the B-ALL, T-ALL and T/B-ALL cases. CONCLUSIONS: The methylation of ID4 promoter region may be related to the pathogenesis of childhood ALL. The methylation patterns of ID4 promoter region are identical in BALL, TALL and T/BALL.[Chin J Contemp Pediatr, 2010, 12 (12):940-942]