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.