Racial Ancestry Research Articles

Post-Transplant Cyclophosphamide-Based Graft-Versus-Host Disease Prophylaxis Attenuates Disparity in Outcomes Between Use of Matched or Mismatched Unrelated Donors.

PURPOSEAccess to allogeneic hematopoietic cell transplantation (HCT) remains limited among persons of non-European ancestry if human leukocyte antigen (HLA) matching is required. We evaluated whether post-transplant cyclophosphamide (PTCy)-based graft-versus-host disease (GVHD) prophylaxis improved HCT outcomes with HLA-matched unrelated donor (MUD) and mismatched unrelated donor (MMUD) HCT when compared with calcineurin inhibitor (CNI)-based prophylaxis.METHODSThree-year overall survival (OS) and GVHD-free, relapse-free survival (GRFS) were compared between adult recipients undergoing initial MUD or single HLA locus MMUD HCT with either PTCy- or CNI-based prophylaxis who were reported to the Center for International Blood and Marrow Transplant Research between 2017 and 2021.RESULTSIncluded were 10,025 HCT recipients (7,272 recipients of MUD with CNI, 1,681 MUD with PTCy, 613 MMUD with CNI, and 459 MMUD with PTCy) who underwent HCT for acute leukemia (70.9%) or myelodysplastic syndromes (29.2%). Median patient age was 60.7 years (range, 18.0-82.7) and median follow-up was 36.6 (range, 3.0-77.8) months. When compared with MUD HCT with PTCy, MMUD HCT with PTCy had similar OS (hazard ratio [HR], 0.96 [95% CI, 0.823 to 1.11]; P = .60) and GRFS (HR, 0.90 [0.79 to 1.02]; P = .1). When compared with MUD HCT with CNI, OS was improved after MUD HCT with PTCy (HR, 0.88 [0.80 to 0.96]; P = .004) and GRFS was improved with PTCy after either MUD (HR, 0.61 [0.57 to 0.66]; P < .0001) or MMUD (HR, 0.68 [0.60 to 0.76]; P < .0001) HCT. Benefit from PTCy was independent of patient ancestry. Global registry level analysis demonstrated that inclusion of MMUD increased donor availability regardless of recipient ancestry.CONCLUSIONUse of PTCy results in comparable OS and GRFS using either MUD or MMUD HCT, expanding access to HCT for patients from all racial and ethnic ancestry groups.

Dominance of African racial ancestry in honey bee colonies of Mexico 30 years after the migration of hybrids from SouthAmerica.

The Africanized honey bee, a hybrid of Apis mellifera scutellata from Africa with European subspecies, has been considered an invasive species and a problem for beekeeping. Africanized bees arrived in Mexico in 1986, 30 years after their accidental release in Brazil. Although government programs were implemented for its eradication, Africanized populations persist in Mexico, but precise information on the patterns of genetic introgression and racial ancestry is scarce. We determined maternal and parental racial ancestry of managed and feral honey bees across the five beekeeping regions of Mexico, using mitochondrial (mtDNA, COI-COII intergenic region) and nuclear markers (94 ancestrally informative SNPs), to assess the relationship between beekeeping management, beekeeping region, altitude, and latitude with the distribution of maternal and parental racial ancestry. Results revealed a predominantly African ancestry in the Mexican honey bees, but the proportion varied according to management, beekeeping regions, and latitude. The Mexican honey bees showed 31 haplotypes of four evolutionary lineages (A, M, C, and O). Managed honey bees had mitochondrial and nuclear higher proportions of European ancestry than feral honey bees, which had a higher proportion of African ancestry. Beekeeping regions of lower latitudes had higher proportions of African nuclear ancestry. Managed and feral honey bees showed differences in the proportion of maternal and nuclear racial ancestry. Managed honey bees from the Yucatan Peninsula and feral honey bees had a higher mtDNA than nuclear proportions of African ancestry. Managed honey bees, except those on the Yucatan Peninsula, had a higher nuclear than mtDNA proportion of African ancestry. Our study demonstrates that Africanized honey bee populations are genetically diverse and well established in Mexico, which highlights the limitations of management and government programs to contain the Africanization process and demands the incorporation of this lineage in any breeding program for sustainable beekeeping.

Abstract C070: BACH1 regulates the hypoxia response and metastasis in triple negative breast cancer

Abstract Triple-negative breast cancer (TNBC), the most aggressive subtype of breast cancer, is more prevalent among African American and underserved female populations. Hypoxia has recently been identified as one of the main drivers of TNBC, particularly within the African American cohort. Therefore, it is important to identify and target key regulators of hypoxia. Here we show that the pro-metastatic transcription factor BACH1 is induced by hypoxia and regulates the hypoxia response in TNBC tumor cells. BACH1 protein is destabilized via an oxygen-dependent prolyl-hydroxylation pathway, akin to Hypoxia-inducible Factors (HIFs). BACH1 mutants (BACH1M) resistant to hydroxylation exhibit heightened transcriptional activity and metastatic potential both in vitro and in vivo. TGCA analysis reveals that TNBC exhibits elevated BACH1 mRNA and hypoxia signature, irrespective of racial ancestry. Nevertheless, racial disparities in BACH1 mRNA expression exist across all breast cancer subtypes (Basal, Her, LumA, LumB). Our findings suggest that BACH1 is an oxygen-sensitive mediator of hypoxia and a promising therapeutic target for mitigating hypoxia-induced pro-metastatic signaling and treatment resistance. These results also highlight the necessity of accounting for racial differences in BACH1 expression and function as a means of developing targeted therapy that takes into account racial disparities in TNBC. Citation Format: Long C. Nguyen, Christopher Dann, Dongbo Yang, Emily Shi, Thomas Li, Leticia Stock, Madeline Henn, Galina Khramtsova, Wenchao Liu, Mitsuyo Matsumoto, Olufunmilayo Olopade, Kazuhiko Igarashi, Marsha Rosner. BACH1 regulates the hypoxia response and metastasis in triple negative breast cancer [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr C070.

Racial and genetic ancestry associations with gene expression patterns in a real-world cohort of colorectal cancer patients.

3541 Background: There is a growing incidence of colorectal cancer (CRC) among young adults and persistent disparities in outcomes by race/ethnicity across all ages. Gene expression signatures, as well as consensus molecular subtypes (CMS) derived from these, have been proposed to predict prognosis and therapy response in CRC. However, it is unclear whether gene expression or CMS are associated with racial disparities observed in CRC. We assessed whether race or genetic ancestry are associated with CMS or gene expression patterns in a deidentified cohort of 1,768 CRC patients. Methods: Patients tumors’ underwent tumor profiling with the Tempus xT NGS 648-gene assay as well as full-transcriptome RNA sequencing. We used a set of 654 ancestry-informative markers to infer genetic ancestry likelihoods for Africa (AFR), America (AMR), East Asia (EAS), Europe (EUR), and South Asia (SAS). Race/ethnicity labels, often missing in real-world data, were imputed using ancestry proportions from the literature and adjusted based on observed metadata. Gene expression data was used to assign CMS to all patients (CMS1, 2, 3, 4 and indeterminate) using CMScaller, and multinomial logistic regression was used to assess associations with race/ethnicity imputed labels and ancestry proportions. We then assessed differential expression (DE) in the MSigDB hallmark and C2 BioCarta gene sets using four separate workflows. The first two workflows used limma-voom followed by ROAST to assess DE among the imputed labels and then among the ancestry proportions (isometric log ratio transformed). The second two workflows used GSVA followed by limma. Results: Among 1,768 patients, 240 were imputed non-Hispanic (NH) Black, 94 NH Asian, 261 Hispanic/Latino/Native American (HLN), and 1,173 NH White. NH Black patients had higher odds of CMS3 vs CMS1 (OR = 2.66, p &lt; 0.001) and HLN patients had higher odds of indeterminate CMS vs CMS1 (OR = 1.90, p = 0.020), compared to NH White. AFR ancestry was significantly associated with CMS3 (OR = 1.05 per doubling in AFR proportion, p = 0.047) and indeterminate CMS (OR = 1.07, p = 0.023). In the gene set analysis, NH Black race/ethnicity was associated with over-expression of the BioCarta WNT pathway gene set. Both AFR ancestry and NH Black race/ethnicity were associated with under-expression of the MSigDB hallmark coagulation and BioCarta alternative complement gene sets and over-expression of the PITX2 pathway gene set (all significant with both ROAST and GSVA). Conclusions: We found that NH Black patients and AFR ancestry were associated with higher rates of CMS3, which is associated with KRAS mutation and was previously reported to be more common among Black patients. Indeterminate CMS associations with AFR ancestry and HLN highlights the need to use diverse patient cohorts when training unsupervised learning models to improve prognosis prediction in non-White patients.

Variability in Pattern of Mutational Signatures in Multiple Myeloma As a Function of Racial Origin

Introduction: Current data suggests Black/African Americans (AA) have an increased risk of developing multiple myeloma (MM), especially in comparison to White/European Americans (EA). However, the underlying causes remain unclear. Genetic definition of the spectrum of acquired mutations and the signatures they contain could help us to understand the mechanism underlying this excess risk. Currently, only limited information is available on the mutational spectra within AAs and the majority of data that has been generated is based on the societal construct of self-identified race/ethnicity alone. To address this deficiency and the potential associated bias, it is critical to examine greater numbers of whole genome sequencing (WGS) data from AAs. Data from a pilot study indicate a prolonged and more intense exposure to the germinal center (GC) reaction in the early evolutionary phases of MM within AAs, suggesting that it is essential to examine sequencing data from early disease stage i.e. smoldering MM (SMM) to better understand genetic predisposition in AAs. Methods: To address the mutational basis of MM and how it varies based on racial origin we carried out two large studies, Polyethnic-1000 and the Smoldering Myeloma Registration Trial (SMRT) study. Furthermore, we examined a cross-sectional series of WGS and whole exome sequencing (WES) data derived from cases with SMM and MM already sequenced to characterize the pattern of mutations and the signatures in both the coding and non-coding regions of the genome. Importantly, to accurately infer racial ancestry, we built an admixture workflow into our sequencing analysis pipeline, enabling us to address the variability in origin from within the MM cases ranging from regions of Europe to subsets of cases with African, North/South American, and Asian origin directly. We showed its use in previous work describing the heterogenous genetic admixture in MM cases that self-identified Hispanic and Latino. Our pipeline uses a suite of well-supported bioinformatic tools for preprocessing sequencing data according to best practices, cataloguing germline variants across a large series of patients, generating ancestry admixture estimations per patient, determining telomere length and composition, and identifying the spectrum of somatic events including single nucleotide variants, small insertions/deletions, copy number variants, and structural variants using consensus calling. All source code and reference data is publicly available via a GitHub repository (https://github.com/pblaney/mgp1000). Results: We generated new WGS data from 65 MM cases (EA n=15, AA n=50), and 44 SMM cases (EA n=36, AA n=18) as part of the Polyethnic 1000 and SMRT study. We also systematically reanalyzed 473 cases with deep (>30x) WGS data and all cases in the CoMMpass study low-depth (5-12x) WGS (n=943). Estimating ancestral composition directly from the genetic data of the CoMMpass study, we identified discrepancies between the self-reported race and the genetically determined admixture composition. Approximately 75% of individuals identified as 'White' but 7% of these cases had a genetic composition that included greater than 10% contribution from African, North/South American, or Asian ancestry. More interesting, 18% identified as 'Black/African American' but 50% of these cases had greater than 10% contribution from European, North/South American, or Asian ancestry. These results demonstrate the underlying genetic heterogeneity in a population that is currently clinically classified as the homogenous and thus lead to skewed evaluations of race and outcome in MM. We will compare the mutational spectra within these groups with different origins to address the risk of developing MM as well as addressing the time of origin of MM within the different populations. Conclusion: We show that there is significant variability of admixture from Europe, North/South America, and Africa within patients who self-identify as White, Black/African American, or Hispanic/Latino in clinical datasets from the U.S. This reinforces the need for complementary genetic admixture with racial self-identification when investigating the links between racial ancestry and outcomes in MM. Figure: Admixture composition of CoMMpass study shows significant contribution of African, North/South American, and East/South Asian origins in predominant European ancestral background. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Biogeographic ancestry information facilitates genetic racial essentialism: Consequences for race‐based judgments

AbstractDirect‐to‐consumer genetic ancestry tests measure biogeographic ancestry (BGA), which refers to an individual's ancestral origin in relation to major population groups. There is growing concern that biogeographic information exaggerates both false beliefs about racial genetic differences and, ultimately, racial bias. Across three studies (N = 1317), we find that biogeographic information impacts racial categorization and beliefs about both genetic racial essentialism (i.e., the extent to which people believe that race is genetically derived) and biological race differences. Specifically, we find people are more likely to categorize Black/White biracial targets as Black and believe that a target is more biologically different from White people (e.g., has thicker skin) as the target's percent sub‐Saharan African biogeographic ancestry (ABGA) increases (Studies 1 and 2). We also find that people misrepresent BGA as “race genes,” such that they perceive Black/White biracial targets with more ABGA as sharing more genes with Black people, which then predicts greater Black racial categorization of the target and increased beliefs that the target is susceptible to certain physical and mental illnesses (Study 2). Notably, BGA remains a predictor of these outcomes even when people know the target's specific racial ancestry, that is, their exact number of Black grandparents (Study 2). Finally, we find that exposing people to the idea that race is genetically derived, compared to biologically derived, exaggerates beliefs that genes determine both human life (genetic essentialism) and racial categories (genetic racial essentialism; Study 3). We discuss implications for studying psychological essentialism, racial bias, and racial health disparities.

EP08.02-014 Impact of East Asian Ancestry on Response to First-Line Osimertinib: A Real-World Canadian Cohort

The phase-III FLAURA clinical trial demonstrated benefit and effectiveness of osimertinib as a first-line treatment for EGFR-mutant NSCLC patients; however, subgroup analysis suggests the magnitude of benefit may differ between Asian and non-Asian patients. Prior real-world data from our institution also suggests EGFR-mutant NSCLC patients of Asian racial ancestry are the most likely to derive benefit from earlier generation EGFR-inhibitors. This study examined real-world clinical population of EGFR-mutant patients treated with first-line osimertinib to compare and contrast the characteristics and response to osimertinib among Asian and non-Asian patients.

Genetic and genomic diversity in the sorghum gene bank collection of Uganda

BackgroundThe Plant Genetic Resources Centre at the Uganda National Gene Bank houses has over 3000 genetically diverse landraces and wild relatives of Sorghum bicolor accessions. This genetic diversity resource is untapped, under-utilized, and has not been systematically incorporated into sorghum breeding programs. In this study, we characterized the germplasm collection using whole-genome SNP markers (DArTseq). Discriminant analysis of principal components (DAPC) was implemented to study the racial ancestry of the accessions in comparison to a global sorghum diversity set and characterize the sub-groups present in the Ugandan (UG) germplasm.ResultsPopulation structure and phylogenetic analysis revealed the presence of five subgroups among the Ugandan accessions. The samples from the highlands of the southwestern region were genetically distinct as compared to the rest of the population. This subset was predominated by the caudatum race and unique in comparison to the other sub-populations. In this study, we detected QTL for juvenile cold tolerance by genome-wide association studies (GWAS) resulting in the identification of 4 markers associated (−log10p > 3) to survival under cold stress under both field and climate chamber conditions, located on 3 chromosomes (02, 06, 09). To our best knowledge, the QTL on Sb09 with the strongest association was discovered for the first time.ConclusionThis study demonstrates how genebank genomics can potentially facilitate effective and efficient usage of valuable, untapped germplasm collections for agronomic trait evaluation and subsequent allele mining. In face of adverse climate change, identification of genomic regions potentially involved in the adaptation of Ugandan sorghum accessions to cooler climatic conditions would be of interest for the expansion of sorghum production into temperate latitudes.

Interstitial lung disease in patients with connective tissue disease: Subtypes, clinical features and comorbidities in the Western Cape, South Africa.

Background Interstitial lung disease (ILD) is highly prevalent in patients with connective tissue disease (CTD) and is poorly characterised in South Africa. Objectives To describe the clinical, serological and radiological features of CTD-ILD and their associations in patients attending a tertiary referral hospital. Methods A cross-sectional study collating clinical, serological and radiological features of CTD-ILD in patients attending rheumatology and respiratory outpatient clinics in a tertiary referral hospital. ResultsOf 124 CTD-ILD patients, 37 (29.8%) had rheumatoid arthritis (RA), 32 (25.8%) systemic sclerosis (SSc) and 55 (44.4%) other autoimmune connective tissue diseases (OCTD). Most patients were female (86.3%), of mixed racial ancestry (75.0%), and the median age was 55 years. Nonspecific interstitial pneumonia (NSIP) was the most common ILD pattern (63.7%), followed by usual interstitial pneumonia (UIP) (26.6%). Overall, 60.5% were current or past smokers, 33.1% had previous pulmonary tuberculosis infection, and 75.6% had gastro-oesophageal reflux disease. Patients with RA were older, had similar frequencies of NSIP and UIP, and had significantly better pulmonary function tests than the SSc and OCTD groups. Within three years of CTD diagnosis, two-thirds of the SSc and OCTD patients and almost half of the RA patients had developed ILD. Clinical features, chest X-rays and pulmonary function tests correlated poorly with high-resolution computerised tomography (HRCT). No case of acute pneumonitis was documented in CTD-ILD patients treated with methotrexate (MTX). Conclusion We suggest routine HRCT in all newly diagnosed CTD patients, particularly those with SSc and OCTD, where more than two-thirds of the patients had developed ILD within three years of their CTD. The use of MTX was not associated with the development of acute pneumonitis in patients with ILD. Key points Clinical features, chest X-rays and pulmonary function tests correlated poorly with high-resolution computerised tomography (HRCT).Smoking, environmental toxins, gastro-oesophogeal reflux and previous pulmonary tuberculosis infection were significant comorbidities in CTD-ILD patients.Early screening of ILD with HRCT is recommended, particularly in SSc.Use of MTX before and after ILD diagnosis was not associated with acute pneumonitis.

Regimes beyond the One-Drop Rule: New Models of Multiracial Identity

The racial classification of mixed-race people has often been presumed to follow hypo- or hyperdescent rules, where they were assigned to either their lower- or higher-status monoracial ancestor group. This simple framework, however, does not capture actual patterns of self-identification in contemporary societies with multiple racialized groups and numerous mixed-race combinations. Elaborating on previous concepts of multiracial classification regimes, we argue that two other theoretical models must be incorporated to describe and understand mixed-race identification today. One is “co-descent”, where multiracial individuals need not align with one single race or another, but rather be identified with or demonstrate characteristics that are a blend of their parental or ancestral races. The other is the “dominance” framework, a modern extension of the “one-drop” notion that posits that monoracial ancestries fall along a spectrum where some—the “supercessive”—are more likely to dominate mixed-race categorization, and others—the “recessive”—are likely to be dominated. Drawing on the Pew Research Center’s 2015 Survey of Multiracial Adults, we find declining evidence of hypo- and hyperdescent at work in the United States today, some support for a dominance structure that upends conventional expectations about a Black one-drop rule, and a rising regime of co-descent. In addition, we explore how regimes of mixed-race classification vary by racial ancestry combination, gender, generation of multiraciality, and the time period in which multiracial respondents or their mixed-race ancestors were born. These findings show that younger, first-generation multiracial Americans, especially those of partial Asian or Hispanic descent, have left hypo- and hyperdescent regimes behind—unlike other young people today whose mixed-race ancestry stems from further back in their family tree.

Mixed-Race Ancestry ≠ Multiracial Identification: The Role Racial Discrimination, Linked Fate, and Skin Tone Have on the Racial Identification of People with Mixed-Race Ancestry

Mixed-race identification may be complex, in that people with mixed-race ancestry may or may not identify as multiracial. Social experiences, such as experiencing racial discrimination, believing that your fate is connected with specific racialized others, and personal characteristics, such as skin color, all have been theorized to play a role in identification. The Mixed-Race Ancestry Survey (2019) conducted on Mechanical Turk allows me to ask unique questions with a large enough sample of this understudied population to disaggregate by racial ancestries. Only people with mixed-race ancestry are included in this study, but respondents may identify mono- or multiracially. Binary logistic regression models reveal that increased linked fate with a specific racial group is associated with greater odds of racially identifying, at least in part, with that group (e.g., among Asians, greater linked fate with Asians is associated with greater odds of identifying as mono- or multiracially Asian). Increased linked fate with multiracials as a group is also connected to greater odds of identifying as multiracial. In addition, personally experiencing racial discrimination is associated with a greater likelihood of identifying as Black and slightly lower odds of identifying as White or as Latinx. Finally, as skin tone darkens the odds of identifying as Black increase three-fold and the odds of identifying as multiracial increase by 1.3 times. I discuss these findings by racial ancestry groups, noting that being aware of having mixed-race ancestry does not in and of itself predict multiracial identification. Rather, in a social structure that uplifts Whiteness, feeling linked fate, experiencing discrimination, and having darker skin tone are important predictors of identification. These findings highlight the mechanisms connected to racial identification for a population that may feel tied to multiple racial groups and is navigating identification within a White-centric nation.

Association of B7-H3 expression with racial ancestry, immune cell density, and androgen receptor activation in prostate cancer.

BackgroundB7 homolog 3 (B7‐H3) is an immunomodulatory molecule that is highly expressed in prostate cancer (PCa) and belongs to the B7 superfamily, which includes PD‐L1. Immunotherapies (antibodies, antibody‐drug conjugates, and chimeric antigen receptor T cells) targeting B7‐H3 are currently in clinical trials; therefore, elucidating the molecular and immune microenvironment correlates of B7‐H3 expression may help to guide trial design and interpretation. The authors tested the interconnected hypotheses that B7‐H3 expression is associated with genetic racial ancestry, immune cell composition, and androgen receptor signaling in PCa.MethodsAn automated, clinical‐grade immunohistochemistry assay was developed by to digitally quantify B7‐H3 protein expression across 2 racially diverse cohorts of primary PCa (1 with previously reported transcriptomic data) and pretreatment and posttreatment PCa tissues from a trial of intensive neoadjuvant hormonal therapy.ResultsB7‐H3 protein expression was significantly lower in self‐identified Black patients and was inversely correlated with the percentage African ancestry. This association with race was independent of the significant association of B7‐H3 protein expression with ERG/ETS and PTEN status. B7‐H3 messenger RNA expression, but not B7‐H3 protein expression, was significantly correlated with regulatory (FOXP3‐positive) T‐cell density. Finally, androgen receptor activity scores were significantly correlated with B7‐H3 messenger RNA expression, and neoadjuvant intensive hormonal therapy was associated with a significant decrease in B7‐H3 protein expression.ConclusionsThe current data underscore the importance of studying racially and molecularly diverse PCa cohorts in the immunotherapy era. This study is among the first to use genetic ancestry markers to add to the emerging evidence that PCa in men of African ancestry may have a distinct biology associated with B7‐H3 expression.Lay Summary B7‐H3 is an immunomodulatory molecule that is highly expressed in prostate cancer and is under investigation in clinical trials.The authors determined that B7‐H3 protein expression is inversely correlated with an individual's proportion of African ancestry.The results demonstrate that B7‐H3 messenger RNA expression is correlated with the density of tumor T‐regulatory cells.Finally, in the first paired analysis of B7‐H3 protein expression before and after neoadjuvant intensive hormone therapy, the authors determined that hormone therapy is associated with a decrease in B7‐H3 protein levels, suggesting that androgen signaling may positively regulate B7‐H3 expression.These results may help to guide the design of future clinical trials and to develop biomarkers of response in such trials.

Hitler’s Northern Utopia: Building the New Order in Occupied Norway

Hitler’s Northern Utopia: Building the New Order in Occupied Norway

Abstract PO-100: Association of B7-H3 expression with racial ancestry, immune cell density and AR activation in prostate cancer

Abstract Background: B7-H3 (CD276, PD-L3) is an immunomodulatory molecule highly expressed in prostate cancer and belonging to the B7 superfamily that also includes PD-L1 (B7-H1). Immunotherapies (antibodies, antibody-drug conjugates, and CAR-T cells) targeting B7-H3 are currently in clinical trials; thus elucidating the clinical, molecular and tumor immune microenvironment correlates of B7-H3 expression may help to guide trial design and interpretation. Methods: We developed an automated, clinical-grade immunohistochemistry assay to digitally quantify B7-H3 protein expression across two racially diverse cohorts of primary prostate cancer (including one with previously reported transcriptomic data), a set of prostatic neuroendocrine small cell carcinoma, and pre- and post-treatment tumor tissues from a trial of intensive neoadjuvant hormonal therapy. Results: B7-H3 protein expression is significantly lower in self-identified Black patients and inversely correlates with percent African ancestry by ancestry-informative markers. This association with race is independent of the significant association of B7-H3 expression with ERG/ETS and PTEN status. CD276 mRNA level, but not B7-H3 protein expression, is significantly correlated with regulatory (FOXP3+) T-cell density. Finally, androgen receptor activity (AR-A) scores are significantly correlated with CD276 mRNA expression, and neoadjuvant intensive hormonal therapy is associated with a significant decrease in B7-H3 protein expression. Conclusion: These data underscore the importance of studying racially and molecularly diverse prostate cancer cohorts in the era of immunotherapy. Our study is among the first to use genetic ancestry markers to add to emerging evidence that prostate tumors from men of African ancestry may have a distinct immune milieu associated with B7-H3 expression. Citation Format: Adrianna A. Mendes, Jiayun Lu, Harsimar B Kaur, Siqun Zheng, Jianfeng Xu, Edward M. Schaeffer, Karen S. Sfanos, Janielle Maynard, Ashley E. Ross, Steven P. Balk, Mary-Ellen Taplin, Emmanuel S. Antonarakis, Corinne E. Joshu, Eugene Shenderov, Tamara L. Lotan. Association of B7-H3 expression with racial ancestry, immune cell density and AR activation in prostate cancer [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PO-100.

Corners, Tables, Lines

Abstract The modern concept of race is usually traced back to proponents of a “natural history of mankind” in the European Enlightenment. Starting from allegorical representations of the four continents in the late sixteenth and seventeenth centuries and the eighteenth-century visual genre of castas paintings, I suggest that modern conceptions of race were significantly shaped by diagrammatic representations of human diversity that allowed for tabulation of data, combinatorial analysis, and quantification, and hence functioned as “tools to think with.” Accounting for racial ancestry in terms of “proportions of blood” not only became a preoccupation of scholars as a consequence, but also came to underwrite administrative practices and popular discourses. To contribute to a better understanding of the history of race relations, historians of the race concept need to pay more attention to these diagrammatic aspects of the concept.

HPV vaccination and factors influencing vaccine uptake among people of Indian ancestry living in the United States.

126 Background: Despite HPV vaccine availability, approximately one-third of annual global cervical cancer deaths occur in India. This may be related to cultural norms that lead to vaccine hesitancy. We sought to determine whether people of Indian ancestry (POIA) who move to the US continue to have disproportionately lower HPV vaccination rates than the rest of the US population and factors that influence HPV vaccine uptake in this group. Methods: The National Health Interview Survey (NHIS) is the largest source of health information for Americans and is designed to be representative of the entire civilian non-institutionalized US population. We utilized the 2018 NHIS to compare HPV vaccine initiation and completion rates between POIA and the general US population and factors correlating with HPV vaccine uptake in this group. Results: There were 17,004 people, representing 185,065,802 in the population, who were between the ages of 18-64 and who responded to questions regarding racial ancestry and HPV vaccination. Of this cohort, 1.69% identified themselves as being of Indian ancestry. Compared to other racial groups, POIA had a significantly lower rate of HPV vaccination (8.18% vs. 12.16%, 14.70%, 16.07%, and 12.41%, in White, Black, Other Asian, and those of other/mixed ancestry, respectively, p = 0.003). However, of those who received one HPV shot there was no difference in vaccine series completion between racial groups (3.17% vs. 4.27%, 3.51%, 4.31%, and 5.04% for POIA vs. White, Black, Other Asian, and those of other/mixed ancestry, respectively, p = 0.465). Among POIA, younger individuals and those who were single were more likely to obtain HPV vaccination (vaccination rates of 38.12%, 6.45% and 1.79% for ages 18-25, 26-45, and 46-64, respectively, p = 0.018, and 29.53% vs. 3.11% for single vs. married, respectively, p = 0.006). All individuals who were vaccinated had some form of health insurance (p = 0.020). Those born in the US had a higher rate of vaccination than those who were not (p = 0.019); however, duration of residence in the US did not influence vaccination rates among POIA (p = 0.502). While high levels of English proficiency were associated with a higher vaccination rate (p = 0.029), education status was not correlated (p = 0.231). Interestingly, both male and female POIA had equivalent rates of vaccination (3.12% and 2.81%, respectively, p = 0.949). Conclusions: POIA are significantly less likely to receive HPV vaccination than the general US population but are equally likely to complete the vaccine series if initiated. Age, insurance status, being born in the US, English speaking proficiency, and marital status significantly influence HPV vaccine initiation among POIA. These data suggest that public health measures promoting HPV vaccination among POIA immigrants may significantly improve vaccination rates among this population.

Gender, Generation, and Multiracial Identification in the United States.

Multiracial self-identification is frequently portrayed as a disproportionately female tendency, but previous research has not probed the conditions under which this relationship might occur. Using the 2015 Pew Survey of Multiracial Adults, we offer a more comprehensive analysis that considers gender differences at two distinct stages: reporting multiple races in one's ancestry and selecting multiple races to describe oneself. We also examine self-identification patterns by the generational locus of multiracial ancestry. We find that females are more likely to be aware of multiracial ancestry overall, but only first-generation females are more likely than their male counterparts to self-identify as multiracial. Finally, we explore the role of racial ancestry combination, finding that multiracial awareness and self-identification are likely gendered differently for different segments of the mixed-race population. This offers a more nuanced picture of how gender interacts with other social processes to shape racial identification in the United States.

A review of White‐centering practices in multiracial research in social psychology

AbstractMultiracial people—those whose racial ancestry is comprised of two or more races—have always had a presence in the United States. However, since the recent US Census shift to allow people to identify with multiple racial groups, social psychologists have shown increased interest in multiracial identity. However, we argue multiracial research tends to emphasize the perceptions, thoughts, and interests of White people through White‐centering research practices, which reproduces racial inequality. To understand how multiracial research within social psychology has been shaped by White‐centering research practices, we reviewed literature in social psychology examining multiraciality. We show that White‐centering practices exist within this literature and explore how White‐centering research practices lead to misrepresentations of the conclusions that may be drawn from multiracial research, underscoring how these conclusions affirm racial power or Whiteness. We suggest Critical Race Psychology as a possible framework to help dismantle the affirmation of Whiteness in multiracial research.

The souls of Black folk (and the weight of Black ancestry) in U.S. Black Americans' racial categorization.

We theorized that from the perspective of U.S. Black Americans, a connection to Black ancestry-and the historical hardship associated with that ancestry-plays an important role in racial categorization. We found support for this across six studies. In Studies 1-3, participants categorized targets with Black ancestry and White experiences or targets with White ancestry and Black experiences. U.S. Black Americans' (more than non-Black Americans') racial categorizations were influenced by Black ancestry (more than by White ancestry). In Study 4, we replicated this effect under extreme conditions (e.g., even when targets had Black ancestry and were phenotypically, socially, culturally, self-identified, and advantaged as White for eighty years, U.S. Black Americans categorized them as Black). In Study 5, U.S. Black Americans were more likely than U.S. White Americans to associate their racial ancestry with hardship, and individual differences in those associations predicted the extent to which U.S. Black Americans categorized the target with Black ancestry and White experiences as Black. In Study 6, participants categorized a target with Black ancestry and ancestral hardship (i.e., their ancestors were kidnapped from Africa and experienced slavery) or a target with Black ancestry and ancestral success (i.e., their ancestors immigrated from Africa and experienced upward mobility). U.S. Black Americans (unlike U.S. White Americans) were more identified with the target with ancestral hardship. Collectively, our research suggests that from the perspective of U.S. Black Americans, the collective Black experiences of the past continue to shape the Black collective of the present. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Ancestry specific associations of a genetic risk score, dietary patterns and metabolic syndrome: a longitudinal ARIC study

BackgroundAssociations have been observed among genetic variants, dietary patterns, and metabolic syndrome (MetS). A gap in knowledge is whether a genetic risk score (GRS) and dietary patterns interact to increase MetS risk among African Americans. We investigated whether MetS risk was influenced by interaction between a GRS and dietary patterns among Whites and African Americans. A secondary aim examined if molecular genetic clusterings differed by racial ancestry.MethodsWe used longitudinal data over 4-visits (1987–1998) that included 10,681 participants aged 45–64y at baseline from the Atherosclerosis Risk in Communities study (8451 Whites and 2230 African Americans). We constructed a simple-count GRS as the linear weighted sum of high-risk alleles (0, 1, 2) from cardiovascular disease polymorphisms from the genome-wide association studies catalog associated with MetS risk. Three dietary patterns were determined by factor analysis of food frequency questionnaire data: Western, healthy, and high-fat dairy. MetS was defined according to the 2016 National Cholesterol Education Program Adult Treatment Panel III criteria but used 2017 American Heart Association/American College of Cardiology criteria for elevated blood pressure. Analyses included generalized linear model risk ratios (RR), 95% confidence intervals (CI), and Bonferroni correction for multiple testing.ResultsThe Western dietary pattern was associated with higher risk for MetS across increasing GRS tertiles among Whites (p < 0.017). The high-fat dairy pattern was protective against MetS, but its impact was most effective in the lowest GRS tertile in Whites (RR = 0.62; CI: 0.52–0.74) and African Americans (RR = 0.67; CI: 0.49–0.91). Among each racial group within GRS tertiles, the Western dietary pattern was associated with development and cycling of MetS status between visits, and the high-fat dairy pattern with being free from MetS (p < 0.017). The healthy dietary pattern was associated with higher risk of MetS among African Americans which may be explained by higher sucrose intake (p < 0.0001). Fewer genes, but more metabolic pathways for obesity, body fat distribution, and lipid and carbohydrate metabolism were identified in African Americans than Whites. Some polymorphisms were linked to the Western and high-fat dairy patterns.ConclusionThe influence of dietary patterns on MetS risk appears to differ by genetic predisposition and racial ancestry.