Replication of neuroblastoma SNP association at the BARD1 locus in African-Americans.

Background: Neuroblastoma is an often fatal pediatric cancer more frequent in European-American than African-American children. African-American children, however, are at higher risk for the more severe form of neuroblastoma and have worse overall survival than European-American children. Genome-wide association studies (GWAS) have identified several single-nucleotide polymorphisms (SNP) associated to neuroblastoma in children of European descent. Knowledge of their association to neuroblastoma in African-American children is still lacking.

Methods: We genotyped and imputed SNPs located in three gene regions reported to be associated to neuroblastoma in children of European descent, and tested them for association in 390 African-American patients with neuroblastoma compared with 2,500 healthy, ethnically matched controls.

Results: SNPs in the BARD1 gene region show a similar pattern of association to neuroblastoma in African-American and European-American children. The more restricted extent of linkage disequilibrium in the African-American population suggests a smaller candidate region for the putative causal variants than previously reported. Limited association was observed at the other two gene regions tested, including LMO1 in 11p15 and FLJ22536 in 6p22.

Conclusions: Common BARD1 SNPs affect risk of neuroblastoma in African-Americans. The role of other SNPs associated to neuroblastoma in children of European descent could not be confirmed, possibly due to different patterns of linkage disequilibrium or limited statistical power to detect association to variants with small effect on disease risk. Extension of GWAS to populations of African descent is important to confirm their results and validity beyond the European populations and can help to refine the location of the putative causal variants.