Genome-wide transethnic meta-analysis identifies novel susceptibility loci for childhood acute lymphoblastic leukemia

Abstract

The incidence patterns of childhood acute lymphoblastic leukemia (ALL) differ across ethnic groups but have been studied mostly in populations of predominantly European ancestries. Risk variants identified from previous genome-wide association studies (GWAS) do not fully explain heritable risk. In an effort to address these limitations, we performed a meta-analysis of ALL in 76,317 participants across four ethnic groups, including 17,814 non-European individuals and 3,482 total cases. We generally replicated previously identified loci associated with ALL (15 out of 16 loci replicated after Bonferroni corrections). We further identified five novel associations at genome-wide significance, including three novel loci and two secondary associations at previously known loci (17q12 and near CEBPE). The three putatively novel loci (rs9376090 near MYB/HBS1L on chr6q23.3, rs10998283 near TET1 on chr10q21.3, and rs9415680 near JMJD1C/NRBF2 on chr10q21.3) were previously shown to be associated with multiple blood cell traits and other hematopoietic cancers. When trans-ethnic information is used, polygenic risk scores constructed from GWAS loci in our trans-ethnic meta-analysis showed similar efficacy in independent Latino (LAT) and non-Latino white (NLW) ALL cohorts (AUC ~ 0.67-0.68) and could partly explain the increased risk of ALL in LAT compared to NLW. Cross-population analysis also showed high but significantly less than 100% genetic correlation between LAT and NLW, suggesting potential differences in the underlying genetic architecture between ethnic groups. In summary, our findings enhance the understanding of genetic contribution to ALL risk across diverse populations and highlight the importance to include multiple ethnic groups in GWAS.