A noncoding regulatory variant in IKZF1 increases acute lymphoblastic leukemia risk in Hispanic/Latino children

Cell Genom. 2024 Apr 10;4(4):100526. doi: 10.1016/j.xgen.2024.100526. Epub 2024 Mar 26.

Abstract

Hispanic/Latino children have the highest risk of acute lymphoblastic leukemia (ALL) in the US compared to other racial/ethnic groups, yet the basis of this remains incompletely understood. Through genetic fine-mapping analyses, we identified a new independent childhood ALL risk signal near IKZF1 in self-reported Hispanic/Latino individuals, but not in non-Hispanic White individuals, with an effect size of ∼1.44 (95% confidence interval = 1.33-1.55) and a risk allele frequency of ∼18% in Hispanic/Latino populations and <0.5% in European populations. This risk allele was positively associated with Indigenous American ancestry, showed evidence of selection in human history, and was associated with reduced IKZF1 expression. We identified a putative causal variant in a downstream enhancer that is most active in pro-B cells and interacts with the IKZF1 promoter. This variant disrupts IKZF1 autoregulation at this enhancer and results in reduced enhancer activity in B cell progenitors. Our study reveals a genetic basis for the increased ALL risk in Hispanic/Latino children.

Keywords: B-ALL; GWAS; IKZF1; Indigenous American; acute lymphoblastic leukemia; cancer disparity; cancer predisposition; childhood leukemia; fine-mapping; hematopoiesis.

MeSH terms

  • Child
  • Genetic Predisposition to Disease* / genetics
  • Hispanic or Latino / genetics
  • Humans
  • Ikaros Transcription Factor / genetics
  • Polymorphism, Single Nucleotide
  • Precursor Cell Lymphoblastic Leukemia-Lymphoma* / genetics
  • Transcription Factors / genetics

Substances

  • Transcription Factors
  • IKZF1 protein, human
  • Ikaros Transcription Factor