Abstract：OBJECTIVE: To examine allelic frequencies of coding single nucleotide polymorphisms (cSNPs) of folypolyglutamate synthetase (FPGS) gene in Chinese Han children with acute leukemia (AL), in order to provide a basis for detecting the relationship between FPGS genetic polymorphisms and tumor individualized chemotherapy. METHODS: cSNPs of exon 5 were detected with polymerase chain reaction (PCR) - denaturing gradient gel electrophoresis (DGGE) in 91 children with AL and 124 children with upper respiratory infection as controls. Genotypes and allelic frequencies were examined. RESULTS: A novel missense mutation, 502/490 T>C (L151/101P), was found in exon 5 of FPGS from control children. The novel mutation was found in mitochondrial variants in two cases and cytosolic variants in three cases. The cytosolic and mitochondrial variants displayed allelic frequencies of 0.70 % and 0.47 % respectively. The novel mutation was not associated with susceptibility to AL. CONCLUSIONS: A novel missense mutation 502/490 T>C (L151/101P) in exon 5 of FPGS gene is firstly found in Chinese Han children, and the cytosolic and mitochondrial variants display allelic frequencies of 0.70 % and 0.47 % respectively.
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