1. Fine-mapping the MHC region in Asian populations identified novel variants modifying susceptibility to lung cancer.
- Author
-
Qin N, Wang C, Zhu M, Lu Q, Ma Z, Huang M, Dai J, Ma H, Jin G, Hu Z, and Shen H
- Subjects
- Alleles, Computational Biology methods, Female, Genome-Wide Association Study, Genotype, Humans, Lung Neoplasms immunology, Major Histocompatibility Complex immunology, Polymorphism, Single Nucleotide, Proportional Hazards Models, Quantitative Trait Loci, Asian People genetics, Chromosome Mapping, Disease Susceptibility, Genetic Variation, Lung Neoplasms genetics, Major Histocompatibility Complex genetics
- Abstract
Objectives: The polymorphic major histocompatibility complex (MHC) plays a vital role in the immune system and drives predisposition to multiple cancers. A number of lung cancer-related genetic variants in the MHC have been identified in recent genome-wide association studies; however, the causal variants remain unclear., Materials and Methods: In the present study, we conducted a large-scale fine-mapping study of lung cancer in the MHC region of 13,945 unrelated Asian individuals to search for potential causal variants. We used the recently constructed Pan-Asian panel as the reference and imputed eight HLA genes (HLA-A, HLC-B, HLA-C, HLA-DRB1, HLA-DQA1, HLA-DQB1, HLA-DPA1, and HLA-DPB1) using SNP2HLA software., Results: We identified one single nucleotide polymorphism, rs12333226 (OR=1.41, P=3.97×10
-7 ), five HLA amino acid polymorphisms in HLA-DRB1 (OR=0.89, P=7.51×10-6 -8.57×10-6 ), and one two-digit classic HLA allele HLA-A*11 (OR=0.87, P=9.68×10-6 ) that were strongly associated with the risk of lung cancer. Rs12333226 was an expression quantitative trait locus of HLA-A and HLA-H in circulating monocytes, and exerted effect on lung cancer risk especially in the younger. HLA-DRβ1 positions 10, 16, and 25 drove the effect of one reported SNP rs2395185. The peptide position analysis identified additional lung cancer susceptibility amino acid positions, including HLA-DRβ1 position 30 and 11 (Pomnibus =6.11×10-5 and 6.91×10-5 ), HLA-DQa1 47 and 76 (Pomnibus =3.96×10-4 and 1.41×10-2 ) and HLA-A 152 (Pomnibus =4.86×10-4 ). Most of the peptide positions were located in the peptide-binding grooves and seemed to affect antigen presentation. All the existing and novel variants explained approximately 2.37% of the phenotypic variances, while 21.10% was attributed to the variants identified in this study., Conclusion: We identified seven novel bi-allelic variants and five polymorphic amino acid positions in HLA-DRβ1, HLA-DQα1, and HLA-A that confer a risk of lung cancer. This finding provides evidence for the substantial contributions of HLA class I and II molecules to lung cancer susceptibility., (Copyright © 2017 Elsevier B.V. All rights reserved.)- Published
- 2017
- Full Text
- View/download PDF