Do African and European ancestry and polymorphism of HLA class I play an important role in controlling HTLV-1 proviral load in admixed cohorts from Salvador, Brazil?

Human leucocyte antigen (HLA) class I molecules present endogenously processed antigens to T-cells and have been linked to differences in HIV-1 disease progression. HLA allelotypes show considerable geographical and inter-individual variation, as does the rate of progression of HIV-1 disease, with long-term non-progression (LTNP) of disease having most evidence of an underlying genetic contribution. However, most genetic analyses of LTNP have occurred in adults of European ancestry, limiting the potential transferability of observed associations to diverse populations who carry the burden of disease. This is particularly true of HIV-1 infected children. Here, using exome sequencing (ES) to infer HLA allelotypes, we determine associations with HIV-1 LTNP in two diverse African pediatric populations. We performed a case-control association study of 394 LTNPs and 420 rapid progressors retrospectively identified from electronic medical records of pediatric HIV-1 populations in Uganda and Botswana. We utilized high-depth ES to perform high-resolution HLA allelotyping and assessed evidence of association between HLA class I alleles and LTNP. Sixteen HLA alleles and haplotypes had significantly different frequencies between Uganda and Botswana, with allelic differences being more prominent in HLA-A compared to HLA-B and C allelotypes. Three HLA allelotypes showed association with LTNP, including a novel association in HLA-C (HLA-B∗57:03, aOR 3.21, Pc = 0.0259; B∗58:01, aOR 1.89, Pc = 0.033; C∗03:02, aOR 4.74, Pc = 0.033). Together, these alleles convey an estimated population attributable risk (PAR) of non-progression of 16.5%. We also observed novel haplotype associations with HLA-B∗57:03-C∗07:01 (aOR 5.40, Pc = 0.025) and HLA-B∗58:01-C∗03:02 (aOR 4.88, Pc = 0.011) with a PAR of 9.8%, as well as a previously unreported independent additive effect and heterozygote advantage of HLA-C∗03:02 with B∗58:01 (aOR 4.15, Pc = 0.005) that appears to limit disease progression, despite weak LD (r2 = 0.18) between these alleles. These associations remained irrespective of gender or country. In one of the largest studies of HIV in Africa, we find evidence of a protective effect of canonical HLA-B alleles and a novel HLA-C association that appears to augment existing HIV-1 control alleles in pediatric populations. Our findings outline the value of using multi-ethnic populations in genetic studies and offer a novel HIV-1 association of relevance to ongoing vaccine studies.

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Association Between Human Leukocyte Antigen Class I and II Diversity and Non-virus-associated Solid Tumors

Frontiers in Genetics ◽

10.3389/fgene.2021.675860 ◽

2021 ◽

Vol 12 ◽

Author(s):

Zhiwei Liu ◽

Allan Hildesheim

Keyword(s):

Human Leukocyte Antigen ◽

Solid Tumors ◽

Genome Wide Association Study ◽

Disease Risk ◽

Human Leukocyte ◽

Hla Class I ◽

Class I ◽

European Ancestry ◽

Leukocyte Antigen ◽

Genome Wide

Homozygosity at human leukocyte antigen (HLA) loci might lead to reduced immunosurveillance and increased disease risk, including cancers caused by infection or of hematopoietic origin. To investigate the association between HLA zygosity and risk of non-virus-associated solid tumors, we leveraged genome-wide association study (GWAS) data from over 28,000 individuals of European ancestry who participated in studies of 12 cancer sites (bladder, brain, breast, colon, endometrial, kidney, lung, ovary, pancreas, prostate, skin, and testis). Information on HLA zygosity was obtained by imputation; individuals were classified as homozygotes at a given locus when imputed to carry the same four-digit allele at that locus. We observed no evidence for an association between zygosity at six HLA loci and all cancers combined. Increase in number of homozygous at HLA class I loci, class II loci, or class I and II loci was also not associated with cancer overall (Ptrend = 0.28), with adjusted odds ratios (ORs) for risk-per-locus of 1.00 [95% confidence intervals (CIs) = 0.97, 1.03], 1.02 (0.99, 1.04), and 1.01 (0.99, 1.02), respectively. This study does not support a strong role for HLA zygosity on risk of non-virus-associated solid tumors.

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HLA Haplotypes Are Associated with Multiple Myeloma Risk in the African American Multiple Myeloma Study (AAMMS)

Blood ◽

10.1182/blood.v128.22.3250.3250 ◽

2016 ◽

Vol 128 (22) ◽

pp. 3250-3250

Author(s):

Loren Gragert ◽

Amie Hwang ◽

Leon Bernal-Mizrachi ◽

Sikander Ailawadhi ◽

Seema Singhal ◽

...

Keyword(s):

Multiple Myeloma ◽

African American ◽

Hla Class I ◽

Hla Typing ◽

Class I ◽

European Ancestry ◽

Sample Sizes ◽

P Values ◽

Hla Alleles ◽

Large Sample

Abstract Background: Persons of African ancestry (AA) have a 2-3-fold higher risk of multiple myeloma (MM) than persons of European ancestry (EA). Like other B-cell malignancies, genome-wide association scans (GWAS) have identified MM risk variants in the HLA region in persons of EA. We conducted a case-control analysis with data from the National Marrow Donor Program (NMDP)1comprising MM patients typed for bone marrow transplant to donor controls matched by race-ethnicity, and found associations between specific HLA alleles/haplotypes and MM risk that varied by race and ethnicity. To confirm our results and identify additional novel signals, we have now investigated associations between HLA alleles and haplotypes and MM risk in the African American Multiple Myeloma Study (AAMMS) Cohort. Methods: The source of subjects was the AAMMS, in which AA MM patients were identified from 10 cancer centers and 4 Surveillance, Epidemiology and End-Results (SEER) Program cancer registries in order to identify genetic risk factors for MM among AAs. A GWAS was conducted using the Illumina Human Core BeadChip array on DNA samples from 1,305 AA MM patients in the AAMMS comparing results to those from 7,078 AA controls with GWAS data generated from the Illumina 1MDuo2. The major histocompatibility complex (MHC) region single nucleotide polymorphisms (SNPs) were imputed to classical HLA variants using HIBAG. Unconditional logistic regression was used to estimate HLA associations, adjusting for sex, age and the first 2 principal components. P-values were adjusted for false discovery rate (FDR) for each locus group. Results: We did not identify any single HLA alleles associated with MM risk among AAs. However, several B*07:02-containing haplotypes were associated with MM risk (odds ratios [OR] ranging from 2.38 to 2.64 and FDR P-values ranging from 1.43 x 10-6 to 3.57 x 10-8). We found associations between MM risk and genotypes containing DRB3*02:02, including DRB3*02:02~DRB1*11:01+ DRB3*02:02~DRB1*11:01 (OR=1.93, PFDR= 9.36 x 10-5) similar to those observed in the NMDP study1. Novel findings included associations between MM risk and HLA Class I haplotypes B*53:01+ B*57:01 (OR=1.94, PFDR= 0.003) and C04:01~B*53:01+C*06:02~B*57:01 (OR=1.96, PFDR= 0.0050). Results from an ongoing meta-analysis between the two data sets (one based on an imputed GWAS and one based on NMDP HLA typing) will be presented. Conclusions: This study is the second to examine HLA alleles and risk of MM among AA's and is by far the largest. We confirmed a previously observed association between an HLA Class II DRB3 variant and MM risk and confirmed an association with B*07 haplotypes previously observed among EAs1. We also identified novel associations between other HLA Class I haplotypes and MM risk in AA's. Because HLA is highly polymorphic, many HLA alleles are rare variants for which genetic associations are difficult to detect without very large sample sizes. Further investigation with large sample sizes will be necessary to refine these associations in order to better identify the underlying causal alleles and determine the functional significance of these HLA associations. 1Beksac M, Gragert L, Fingerson S, et al.: HLA polymorphism and risk of multiple myeloma.Leukemia. 2016 Jul 27. doi: 10.1038/leu.2016.199. 2Rand KA, Song C, Hwang AE, et al. Genetic susceptibility markers of multiple myeloma in African-Americans. Abstract # 2030, 56th Annual American Society of Hematology Meeting, San Francisco, California, 2014. Disclosures Ailawadhi: Pharmacyclics: Consultancy; Novartis: Consultancy; Amgen Inc: Consultancy; Takeda Oncology: Consultancy. Nooka:Spectrum, Novartis, Onyx pharmaceuticals: Consultancy. Zonder:Pharmacyclics: Other: DSMC membership; Prothena: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Research Funding; Bristol Myers Squibb: Consultancy, Honoraria; Seattle Genetics: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Janssen: Consultancy, Honoraria. Lonial:BMS: Consultancy; Novartis: Consultancy; Millenium: Consultancy; Celgene: Consultancy; Janssen: Consultancy; Merck: Consultancy; Celgene: Consultancy; BMS: Consultancy; Novartis: Consultancy; Onyx: Consultancy; Janssen: Consultancy; Onyx: Consultancy.

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