A two-stage evaluation of genetic variation in immune and inflammation genes with risk of non-Hodgkin lymphoma identifies new susceptibility locus in 6p21.3 region.

BACKGROUND

Non-Hodgkin lymphoma (NHL) is a malignancy of lymphocytes, and there is growing evidence for a role of germline genetic variation in immune genes in NHL etiology.

METHODS

To identify susceptibility immune genes, we conducted a 2-stage analysis of single-nucleotide polymorphisms (SNP) from 1,253 genes using the Immune and Inflammation Panel. In Stage 1, we genotyped 7,670 SNPs in 425 NHL cases and 465 controls, and in Stage 2 we genotyped the top 768 SNPs on an additional 584 cases and 768 controls. The association of individual SNPs with NHL risk from a log-additive model was assessed using the OR and 95% confidence intervals (CI).

RESULTS

In the pooled analysis, only the TAP2 coding SNP rs241447 (minor allele frequency = 0.26; Thr655Ala) at 6p21.3 (OR = 1.34, 95% CI 1.17-1.53) achieved statistical significance after accounting for multiple testing (P = 3.1 × 10(-5)). The TAP2 SNP was strongly associated with follicular lymphoma (FL, OR = 1.82, 95%CI 1.46-2.26; p = 6.9 × 10(-8)), and was independent of other known loci (rs10484561 and rs2647012) from this region. The TAP2 SNP was also associated with diffuse large B-cell lymphoma (DLBCL, OR = 1.38, 95% CI 1.08-1.77; P = 0.011), but not chronic lymphocytic leukemia (OR = 1.08; 95% CI 0.88-1.32). Higher TAP2 expression was associated with the risk allele in both FL and DLBCL tumors.

CONCLUSION

Genetic variation in TAP2 was associated with NHL risk overall, and FL risk in particular, and this was independent of other established loci from 6p21.3.

IMPACT: Genetic variation in antigen presentation of HLA class I molecules may play a role in lymphomagenesis.