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Published on: August 20, 2019

MDR1 gene variants, indoor insecticide exposure, and the risk of childhood acute lymphoblastic leukemia

Kevin Y Urayama1, John K Wiencke, Patricia A Buffler

  • 1Department of Epidemiology and Biostatistics, University of California, San Francisco, CA 94143-0560, USA.

Cancer Epidemiology, Biomarkers & Prevention : a Publication of the American Association for Cancer Research, Cosponsored by the American Society of Preventive Oncology
|June 6, 2007
PubMed

Insights

Children with a specific genetic marker (haplotype CGC) may have reduced risk of childhood acute lymphoblastic leukemia (ALL) from indoor insecticide exposure. This suggests a potential gene-environment interaction influencing ALL susceptibility.

Area of Science:

  • Genetics
  • Environmental Health
  • Pediatric Oncology

Background:

  • The multidrug resistance (MDR) 1 gene encodes P-glycoprotein, a transporter involved in cellular defense against xenobiotics.
  • Single nucleotide polymorphisms (SNPs) and haplotypes in MDR1 may influence susceptibility to environmental exposures.
  • Childhood acute lymphoblastic leukemia (ALL) risk is potentially influenced by genetic factors and environmental exposures like insecticides.

Purpose of the Study:

  • To investigate the association between MDR1 genetic variations (SNPs and haplotypes) and childhood ALL risk.
  • To determine if MDR1 genetic variations modify the relationship between indoor insecticide exposure and childhood ALL risk.

Main Methods:

  • Genotyping of four MDR1 SNPs (T-129C, C1236T, G2677T/A, C3435T) in childhood ALL cases (n=294) and controls (n=369).
  • Whole genome amplification of buccal cell DNA.
  • Detailed in-home interviews to collect data on household pesticide use.

Main Results:

  • MDR1 SNPs individually or as haplotypes were not significantly associated with childhood ALL.
  • A significant interaction was observed between indoor insecticide exposure and the CGC haplotype (interaction OR, 0.31; P=0.025).
  • Carriers of the CGC haplotype showed a reduced risk of ALL associated with indoor insecticide exposure.

Conclusions:

  • Preliminary findings suggest that the CGC haplotype may confer protection against the leukemogenic effects of indoor insecticide exposure in children.
  • These results indicate a potential gene-environment interaction in the etiology of childhood ALL.
  • Further research is warranted to validate these findings and explore the underlying mechanisms.
Abstract

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