ABSTRACT
To investigate the correlation between cytotoxic T lymphocyte antigen-4 [CTLA-4] gene polymorphism and children with acute lymphoblastic leukemia [ALL]
A total of 86 children of ALL [23 HR, 54SR] and 112 healthy controls was selected. The genptypes were determined by means of polymerase chain reaction [PCR] and the PCR product sequencing. Genotype and alleles frequency of SNP-318, SNP+49 and SNP-CT60 were compares among different groups
The frequency of TC,TT genotype and T allele in ALL children at SNP-318 position were statistically higher than controls. In HR group, the frequency of TC, TT genotype at SNP-318 position was statistically higher than SR group. There was no significantly difference in genotype and allele distribution of SNP+49 position among the HR patients, SR patients and control group. [2] The frequency of GG genotype and G allele in ALL children at SNP-CT60 position were significantly higher than controls. The genotype and allele distribution of SNP-CT60 position between different clinical risk groups were no significantly different. As a result of the increased frequency of TC, TT genotype and T allele at SNP-318, ALL children synthesized more CTLA-4 to deliver the inhibitive signal, and this lead to restraint of T cell activation. Such difference at SNP-318 position was obvious in HR children
The SNP+49 position is probably not the main regulating point in ALL. [2] In SNP-CT60 position, the G allele played the main part
The increase of G allele frequency result in the high expression of CTLA-4. such difference at SNP-318 position was obvious in HR children