Implication of Genetic Variations of Ikzf1, ARIDB5, and CEBPE Genes In the Risk of Childhood Acute Lymphoblastic Leukemia In Korea

Recent western studies have showed the implication of the germline genomic variations in IKZF1 gene at 7p12.2, ARIDB5 gene at 10q21.2, and CEBPE gene at 14q11.2 on the risk of childhood acute lymphoblastic leukemia (ALL); the most significant association was observed in the single nucleotide polymorphism (SNP) rs4132601 which located at 3' region of the IKZF1. IKZF1 plays important role in lymphocyte differentiation, proliferation and function, ARIDB5 in embryogenesis and growth regulation, and CEBPE in regulation of myelopoiesis. Genomic variants in these genes are therefore considered to be involved in transcriptional regulation and differentiation of B cell progenitors. However, there have been no reports on the role of germline variations in leukemogenesis of childhood ALL in Asian countries. The aim of this study is to show the impact of these genetic variants on childhood ALL in Korea.

To examine the association between genetic variations (IKZF1 rs4132601, ARIDB5 rs7089424, and CEBPE rs2239633) and the risk of childhood ALL, we here analyzed 228 children with ALL and 508 healthy individuals in Korea.

In ARIDB5 rs7089424, TG and GG genotypes were significantly associated with a risk for ALL (odds ratio [OR], 1.63; 95% confidential interval [CI], 1.07–2.48; P=0.02 for TG genotype, OR, 2.69; 95% CI, 1.42–5.07; P=0.002 for GG genotype). The allele incidence of ARIDB5 rs7089424 was also significantly associated with a risk for ALL (OR, 1.66; 95% CI, 1.24–2.22; P=0.0006). CEBPE rs2239633 TT genotype showed a significant association with a decreased risk for ALL (OR, 0.54; 95% CI, 0.33–0.90; P=0.02 for TT genotype). The allele incidence of CEBPE rs2239633 was also associated with a decreased risk for ALL (OR, 0.77; 95% CI, 0.61–0.97; P=0.02). There was no significant association between IKZF1 rs4132601 polymorphism and a risk for ALL in this study.

These results suggest that genomic variations of ARIDB5 and CEBPE may play an important role in the risk for childhood ALL in Korea, compared with findings from western countries showing a significant relation between IKZF1 and childhood ALL. Several factors should be considered to explain a discrepancy between our results and the previous studies, which include different genotype frequencies in polymorphisms and varied susceptibility to ALL in different ethnic groups. Further studies incorporating larger number of cases and analyzing other SNPs or other Asian countries are warranted in childhood ALL.

No relevant conflicts of interest to declare.