Pedigree Analysis Research Articles

Under the name of “Lua”: revisiting genetic heterogeneity and population ancestry of Austroasiatic speakers in northern Thailand through genomic analysis

BackgroundAustroasiatic (AA)-speaking populations in northern Thailand are of significant interest due to their status as indigenous descendants and their location at the crossroads of AA prehistoric distribution across Southern China, the Indian Subcontinent, and Mainland Southeast Asia. However, the complexity of ethnic identification can result in inaccuracies regarding the origin and migration history of these populations. To address this, we have conducted a genome-wide SNP analysis of 89 individuals from two Lavue and three Lwa-endonym populations. We then combined our outcomes with previously published data to elucidate the genetic diversity and clustering of AA groups in northern Thailand.ResultsOur findings align with existing linguistic classifications, revealing different genetic compositions among the three branches of the Mon-Khmer subfamily within the AA family: Monic, Khmuic, and Palaungic. Although the term “Lua” ethnicity is confusingly used to identify ethnic groups belonging to both Khmuic and Palaungic branches, our genomic data indicate that the Khmuic-speaking Lua living on the eastern side of the region are relatively distant from the Palaungic-speaking Lavue and Lwa populations living on the western side. The Lavue populations, primarily inhabiting mountainous areas, exhibit a genetic makeup unique to the AA family, with a close genetic relationship to the Karenic subgroup of the Sino-Tibetan language family. Conversely, the Lwa and Blang populations, residing in lowland river valleys, display genetic signatures resulting from admixture with Tai-Kadai-speaking ethnic groups.ConclusionUtilizing genome-wide SNP markers, our findings indicate genetic heterogeneity among the Lua, Lavue, and Lwa ethnic groups. The intricate interplay of genetics, cultural heritage, and historical influences has shaped these ethnic communities. Our study underscores the importance of accurate ethnic classifications, emphasizing the use of self-identified endonyms, names created and used by the ethnic groups themselves. This approach respects the AA communities in northern Thailand and acknowledges their significant contributions to advancing our understanding of genetic anthropology.

Relation of CMV and brain atrophy to trajectories of immunosenescence in diverse populations.

Immunosenescence (ISC), the aging of the immune system, has largely been studied in populations of European descent. Here, circulating immune cell cytometric data from African-American, Hispanic, and non-Hispanic White participants were generated. Known and novel age effects were identified using either a meta-analysis approach or a parallel genetic approach. Most results are consistent across the three populations, but some cell populations display evidence of heterogeneity, such as a PD-L1 + CD56 + NK cell subset. The study estimated "Immunological Age" (IA) during physiologic aging. While we found no relation of IA to Multiple Sclerosis, IA is associated with entorhinal cortex atrophy, a presymptomatic feature of Alzheimer's disease, linking neurodegeneration and peripheral immunity. ISC trajectories were also inferred, highlighting age, CMV status, and genetic ancestry as key influences. Our assessment offers reference ISC trajectories for personalization of assessments of immune function over the life course in diverse populations.

Clinical and genetic analysis of a Chinese pedigree affected with type 2 Long QT syndrome due to variant of KCNH2 gene

To explore the clinical and genetic etiology of a Chinese pedigree affected with type 2 Long QT syndrome (LQTS). A pedigree with type 2 LQTS presented at Fuwai Central China Cardiovascular Hospital on August 23, 2019 was selected as the study subject. Peripheral blood samples were collected from the proband and her parents. Following extraction of genomic DNA, whole exome sequencing (WES) was carried out for the proband, and candidate variant was screened through functional annotation and protein-protein interaction (PPI) analysis. Sanger sequencing was conducted to verify the pathogenicity of candidate variant. This study was approved by the Fuwai Central China Cardiovascular Hospital (Ethics No. 2019-15). WES revealed that the proband has harbored a missense variant of the KCNH2 gene, namely c.1478A>G (p.Tyr493Cys), which was confirmed by Sanger sequencing to have inherited from her father. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was classified as likely pathogenic (PM2_supporting+PM5+PP3+PP4). The KCNH2 gene c.1478A>G (p.Tyr493Cys) variant probably underlay the type 2 LQTS in this pedigree.

Clinical and genetic analysis of a Chinese pedigree affected with Familial focal epilepsy with variable foci due to variant of NPRL3 gene

To explore the clinical manifestations and genetic etiology of a Chinese pedigree affected with Familial focal epilepsy with variable foci (FFEVF). A FFEVF pedigree presented at the Department of Medical Genetics of Linyi Maternal and Child Health Care Hospital on March 14, 2023 was selected as the study subject. The proband was subjected to whole exome sequencing (WES). Candidate variants were verified by Sanger sequencing of the proband and other affected members and bioinformatic analysis. This study was approved by the Linyi Maternal and Child Health Care Hospital (Ethics No. QTL-YXLL-2023048). WES revealed that the proband has harbored a heterozygous c.1642C>T (p.Arg548Cys) missense variant in exon 15 of the NPRL3 gene. Sanger sequencing confirmed that the variant was inherited from the proband's father, and multiple members of the pedigree had also harbored the same variant. Based on guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was classified as variant of unknown significance (PM2_supporting + PP3). The clinical phenotype of FFEVF patients caused by variants of NPRL3 gene is extensive, and the patients may present with neurological abnormality of autism spectrum disorder in addition to seizures.

Genetic analysis and prenatal diagnosis of a Chinese pedigree affected with Complete androgen insensitivity syndrome due to a novel variant of AR gene

To explore the clinical and molecular basis for a Chinese pedigree affected with Complete androgen insensitivity syndrome (CAIS). A CAIS pedigree presented at Tianjin Medical University General Hospital between 2019 and 2021 was selected as the study subject. Clinical data of the proband was collected, along with peripheral blood samples from the proband and her family members. Chromosomal karyotyping, sex-determining region of the Y chromosome (SRY) testing, and next-generation sequencing (NGS) were carried out for the proband, and candidate variant was verified by Sanger sequencing of her family members. Prenatal diagnosis was provided for the sister of the proband. This study was approved by the Tianjin Medical University General Hospital (Ethics No. IRB2023-WZ-070). The 18-year-old proband, who has a social gender of female, underwent laparoscopic examination, which showed no presence of uterus and ovaries. The karyotype of peripheral blood sample was 46,XY, with SRY gene detected. NGS indicated that the proband has harbored a heterozygous c.1988C>G (p.Ser663Ter) variant of the AR gene. Sanger sequencing confirmed that her mother and sister had both harbored the same variant, whilst her father and younger sister were of the wild-type. Prenatal diagnosis revealed that her sister's first fetus had harbored carried the same variant, which had led to termination of pregnancy. Her second fetus did not carry the variant, and a healthy boy was born. Based on guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was classified as likely pathogenic (PM2_Supporting+PM4+PP3_Moderate+PP4). The c.1988C>G (p.Ser663Ter) variant of the AR gene probably underlay the CAIS in the proband. The accurate diagnosis of sex development disorders will rely on the physicians' thorough understanding of the clinical symptoms and pathogenic genes. Genetic testing and counseling can enable precise diagnosis, prenatal diagnosis, and guidance for reproduction.

Development and evaluation of a panel of newly screened Y chromosome InDels for inferring paternal ancestry information in Southwest China.

Y-InDels (insertions/deletions) are genetic markers which are extremely understudied. It is unknown whether this type of markers can be utilized for genetic ancestry inference. We have developed an innovative Y chromosome ancestry inference system tailored for forensic applications. This panel amplifies 21 Y chromosome loci, encompassing Y-InDels and Y-SNPs (Single Nucleotide Polymorphism), utilizing the capillary electrophoresis (CE) platform. The system performed well at DNA concentrations greater than 0.125 ng/ul and produced accurate results at a 1:100 mixing ratio of male and female DNA. The Cumulative probability of matching (CPM) was between 0.95 and 0.97 in the experimental population. The system's efficacy in inferring ancestral origins was demonstrated through intercontinental population discrimination, revealing high discrimination power between African and East Asian populations. Population genetic analyses conducted on Han, Qiang and Hui populations in Southwest China, where the smallest FST value was 0.0002 between Han Chinese in Beijing (from 1000 Genomes Project) and Qiang Chinese from Sichuan (CQSC). Phylogenetic tree construction further illuminated distinct haplotypes among populations, with ethnically unique haplotypes observed in 34.6% of Hui and 7.1% of Qiang populations. K-fold cross-validation show the system's inference abilities at the intercontinental level. In addition, our investigations identified potential associations between the Y-InDel locus Y: 15,385,547 (GRCh37) and haplogroup R1a1a1b2a2- Z2124, as well as locus Y: 13,990,180 (GRCh37) and haplogroup F-M89. In conclusion, we have established a Y-chromosome inference system tailored for grassroots-level application, underscoring the value of incorporating Y-InDel markers in forensic analyses.

GestaltMatcher Database - A global reference for facial phenotypic variability in rare human diseases.

The most important factor that complicates the work of dysmorphologists is the significant phenotypic variability of the human face. Next-Generation Phenotyping (NGP) tools that assist clinicians with recognizing characteristic syndromic patterns are particularly challenged when confronted with patients from populations different from their training data. To that end, we systematically analyzed the impact of genetic ancestry on facial dysmorphism. For that purpose, we established the GestaltMatcher Database (GMDB) as a reference dataset for medical images of patients with rare genetic disorders from around the world. We collected 10,980 frontal facial images - more than a quarter previously unpublished - from 8,346 patients, representing 581 rare disorders. Although the predominant ancestry is still European (67%), data from underrepresented populations have been increased considerably via global collaborations (19% Asian and 7% African). This includes previously unpublished reports for more than 40% of the African patients. The NGP analysis on this diverse dataset revealed characteristic performance differences depending on the composition of training and test sets corresponding to genetic relatedness. For clinical use of NGP, incorporating non-European patients resulted in a profound enhancement of GestaltMatcher performance. The top-5 accuracy rate increased by +11.29%. Importantly, this improvement in delineating the correct disorder from a facial portrait was achieved without decreasing the performance on European patients. By design, GMDB complies with the FAIR principles by rendering the curated medical data findable, accessible, interoperable, and reusable. This means GMDB can also serve as data for training and benchmarking. In summary, our study on facial dysmorphism on a global sample revealed a considerable cross ancestral phenotypic variability confounding NGP that should be counteracted by international efforts for increasing data diversity. GMDB will serve as a vital reference database for clinicians and a transparent training set for advancing NGP technology.

Incorporating multiracial and multiethnic experiences into genetic counseling practice and research: A necessary opportunity.

The conflation of race and genetic ancestry can have harmful consequences. Biological conceptualizations of race have long been used to justify inequities and distract from social structures that afford opportunities to some that are unjustly denied to others. Despite recent efforts within the scientific community to distinguish between the sociopolitical constructs of race and ethnicity and the biological constructs of genetic ancestry and genetic similarity, their conflation continues to influence genomic research and its translation into clinical care. One overlooked aspect of this problematic conflation is the extent to which discrete monoracial and monoethnic categorization systems persist and perpetuate unequal benefit-sharing in the clinical translation of genomic technologies. In genetic service delivery, reliance on discrete racial and ethnic categories undermines the clinical translation of genomic technologies for large segments of the global population. For multiracial and multiethnic individuals, who have complex identities that defy discrete categorization systems, the potential benefits of genomic discoveries are especially elusive. Scholars have recently begun to call for the inclusion of multiracial, multiethnic, and admixed individuals in race, ethnicity, and ancestry frameworks in genetics and genomics. However, little work has been done to explore and address the unique challenges and opportunities posed by multiracial/multiethnic individuals in genetic counseling specifically. We discuss how conceptualizing diversity along discrete racial and ethnic lines perpetuates inequitable patient care and limits efforts to increase inclusion and belonging within genetic counseling. Moreover, we argue that ongoing efforts to mitigate racial inequity must actively challenge the paradigm of monoracial and monoethnic categories to accomplish their goal.

Unveiling ancestral threads: Exploring CCR5 ∆32 mutation frequencies in Colombian populations for HIV/AIDS therapeutics

AIDS remains a significant global health challenge since its emergence in 1981, with millions of deaths and new cases every year. The CCR5 ∆32 genetic deletion confers immunity to HIV infection by altering a cell membrane protein crucial for viral entry. Stem cell transplants from homozygous carriers of this mutation to HIV-infected individuals have resulted in viral load reduction and disease remission, suggesting a potential therapeutic avenue. This study aims to investigate the relationship between genetic ancestry and the frequency of the CCR5 ∆32 mutation in Colombian populations, exploring the feasibility of targeted donor searches based on ancestry composition. Utilizing genomic data from the CÓDIGO-Colombia consortium, comprising 532 individuals, the study assessed the presence of the CCR5 ∆32 mutation and examined if the population was on Hardy-Weinberg equilibrium. Individuals were stratified into clusters based on African, American, and European ancestry percentages, with logistic regression analysis performed to evaluate the association between ancestry and mutation frequency. Additionally, global genomic databases were utilized to visualize the worldwide distribution of the mutation. The findings revealed a significant positive association between European ancestry and the CCR5 ∆32 mutation frequency, underscoring its relevance in donor selection. African and American ancestry showed negative but non-significant associations with CCR5 ∆32 frequency, which may be attributed to the study's limitations. These results emphasize the potential importance of considering ancestry in donor selection strategies, reveal the scarcity of potential donors in Colombia, and underscore the need to consider donors from other populations with mainly European ancestry if the CCR5 ∆32 stem cell transplant becomes a routine treatment for HIV/AIDS in Colombia.

6527 Genetic variants may influence the glycemic response to sodium-glucose cotransporter-2 inhibitors in the Mass General Brigham Biobank

Abstract Disclosure: J.H. Li: None. A. Barry: None. A. Huerta-Chagoya: None. L. Szczerbinski: None. J.M. Mercader: None. J.C. Florez: Consulting Fee; Self; AstraZeneca. Grant Recipient; Self; Novo Nordisk. Speaker; Self; Novo Nordisk, Merck. A. Leong: None. Background: Sodium-glucose cotransporter-2 inhibitors (SGLT2i) are increasingly prescribed for the treatment of type 2 diabetes, but there is interindividual variability in glycemic response. We investigated whether two genetic variants, rs33954001, a missense variant (p.His615Gln) in SLC5A1 encoding SGLT1, and rs8050500 near SLC5A2 encoding SGLT2, previously associated with glycemic traits in genome-wide association studies, had any influence on short-term glycated hemoglobin (HbA1c) lowering in patients on SGLT2i treatment. Methods: We identified 1,961 ancestrally diverse, genotyped individuals with documented exposure to a SGLT2i in the Mass General Brigham Biobank, a hospital-based biobank linked with patient medical records. Of these, 736 individuals had a baseline HbA1c ≥ 6% within 6 months of the index appearance of an SGLT2i and a follow-up HbA1c measured 6-12 months after. Genotyping was performed on the Illumina Multi-Ethnic Genotyping Array and the Illumina Global Screening Array. Variants were imputed with the TOPMed reference panel. Using linear regression models, we evaluated the additive effect of the genetic variants on HbA1c reduction, defined as baseline HbA1c minus follow-up HbA1c, adjusted for age, sex, 10 genetic ancestry principal components to account for population stratification, the number of concomitant glucose-lowering drug classes, and three covariates accounting for potential genotyping batch effects. To determine whether genetic effects varied by pretreatment glycemic control, we tested for a genotype × baseline HbA1c interaction and performed stratified analysis by baseline HbA1c (≥ 8% vs. < 8%). Results: The mean age of participants was 63.7 years and 41% were female. The baseline HbA1c was 8.0 ± 1.9%. The mean HbA1c reduction was 0.6% over a mean follow-up time of 8.7 ± 1.6 months. None of the variants were associated with HbA1c reduction (p > 0.05) in the whole dataset. However, in stratified analyses, among those with baseline HbA1c ≥ 8% (n = 382), we observed that carriers of the G allele at rs33954001 had a 0.5% greater HbA1c reduction (p = 0.048) compared to those with CC genotype. Further adjustment for baseline renal function did not modify results. In the Genotype-Tissue Expression (GTEx) portal, the G allele was associated with higher SLC5A1 expression in nerve (p = 1 × 10-8), esophageal mucosa (p = 4 × 10-5) and stomach (p = 9 × 10-5), but not kidney. In the Translational human pancreatic Islet Genotype tissue-Expression Resource (TIGER), the G allele was associated with SLC5A1 expression in pancreatic islets (p = 2 × 10-6). Conclusion: Genetic variation in SLC5A1 may partly explain heterogeneity in SGLT2i treatment effects among people with sub-optimally controlled diabetes, possibly due to differences in SLC5A1 tissue-specific expression. These findings require validation in large hospital-based biobanks or dedicated clinical trials. Presentation: 6/2/2024

Genetic African ancestry modifies the biology of acute myeloid leukemia.

Genetic African ancestry modifies the biology of acute myeloid leukemia.

Association of genetic ancestry with pre-eclampsia in multi-ethnic cohorts of pregnant women

ObjectivesMaternal self-reported ethnicity is recognised as a risk factor for pre-eclampsia in clinical screening tools and models. This study investigated whether ethnicity is acting as a proxy for genetic variants in this context. Study designA total of 436 women from multi-ethnic backgrounds recruited to two UK observational pregnancy hypertension cohort studies were genotyped. Genetically-computed individual ancestry estimates were calculated for each individual through comparison to the multi-ethnic 1000 Genomes reference panel genotypes. Regression models for pre-eclampsia using clinical risk factors including self-reported ethnicity with and without ancestry estimates were built and compared using Likelihood Ratio Tests (LRT). Main outcome measuresPre-eclampsia (early- and late-onset). ResultsIn these multi-ethnic cohorts (mean age 34.9 years; 41.3 % White, 34.2 % Black, 13.1 % Asian ethnic backgrounds; 82.6 % chronic hypertension), discrepancies between self-reported ethnicity and genetically-computed individual ancestry estimates were present in all ethnic groups, particularly minority groups. Genetically-computed pan-African ancestry percentage was associated with early-onset (< 34 weeks) pre-eclampsia in adjusted models (aOR 100 % vs 0 % African ancestry: 3.81, 95 % CI 1.04–14.14, p-value 0.044) independently of self-reported ethnicity and established clinical risk factors. Addition of genetically-computed African ancestry to a clinical risk factor model including self-reported ethnicity, improved model fit (Likelihood ratio test p-value 0.023). ConclusionsSelf-reported maternal ethnicity is an imperfect proxy for genetically-computed individual ancestry estimates, particularly in ethnic minority groups. Genetically-computed African ancestry percentage was associated with early-onset pre-eclampsia independently of self-reported maternal ethnicity. Well-powered studies in multi-ethnic cohorts are required to delineate the genetic contribution to pre-eclampsia.

Genetic diversity and origin of Kazakh Tobet Dogs

The Kazakh Tobet is an indigenous Kazakh dog breed that has been used to guard livestock since ancient times. To understand the genetic structure and phylogenetic relationship of the Kazakh Tobet breed with other herding and livestock guarding dog breeds, we analysed short tandem repeat data of 107 Kazakh Tobet dogs from different regions of Kazakhstan and Mongolia, as well as whole genome sequencing data from two Kazakh Tobet dogs and 43 dogs from 24 working breeds. Our results indicate a high genetic diversity of the Kazakh Tobet, with the average number of alleles per locus ranging from 6.00 to 10.22 and observed heterozygosity ranging from 76 to 78%. The breed has a complex genetic structure characterised by seven different clusters. The neighbour-joining tree constructed based on 14,668,406 autosomal and the maximum likelihood tree based on mitochondrial D-loop sequences indicate a common genetic heritage between the Kazakh Tobet, the Central Asian Shepherd Dog and the Turkish Akbash. The presence of haplotype A18 in the Kazakh Tobets supports the hypothesis of the ancient origin of the breed, which was previously suggested by archaeological finds and written sources. These results provide an important genetic basis for the ongoing efforts to improve the Kazakh Tobet breed, to ensure its preservation as an independent genetic lineage and to recognise a breed on an international level.

Molecular profile of driver genes in lung adenocarcinomas of Brazilian patients who have never smoked: implications for targeted therapies.

Lung cancer in never-smoker (LCINS) patients accounts for 20% of lung cancer cases, and its biology remains poorly understood, particularly in genetically admixed populations. We elucidated the molecular profile of driver genes in Brazilian LCINS. The mutational and gene fusion status of 119 lung adenocarcinomas from self-reported never-smoker patients, was assessed using targeted sequencing (NGS), nCounter, and immunohistochemistry. A panel of 46 ancestry-informative markers determined patients' genetic ancestry. The most frequently mutated gene was EGFR (49.6%), followed by TP53 (39.5%), ALK (12.6%), ERBB2 (7.6%), KRAS (5.9%), PIK3CA (1.7%), and less than 1% alterations in RET, NTRK1, MET∆ex14, PDGFRA, and BRAF. Except for TP53 and PIK3CA, all other alterations were mutually exclusive. Genetic ancestry analysis revealed a predominance of European (71.1%), and a higher African ancestry was associated with TP53 mutations. Brazilian LCINS exhibited a similar molecular profile to other populations, except the increased ALK and TP53 alterations. Importantly, 73% of these patients have actionable alterations that are suitable for targeted treatments.

Multiple measures for self-identification improve matching donors with patients in unrelated hematopoietic stem cell transplant

BackgroundQuestions persist around whether and how to use race or geographic ancestry in biomedical research and medicine, but these forms of self-identification serve as a critical tool to inform matching algorithms for human leukocyte antigen (HLA) of varying levels of resolution for unrelated hematopoietic stem cell transplant in large donor registries.MethodsHere, we examined multiple self-reported measures of race and ancestry from a survey of a cohort of over 100,000 U.S. volunteer bone marrow donors alongside their high-resolution HLA genotype data.ResultsWe find that these self-report measures are often non-overlapping, and that no single self-reported measure alone provides a better fit to HLA genetic ancestry than a combination including both race and geographic ancestry. We also found that patterns of reporting for race and ancestry appear to be influenced by participation in direct-to-consumer genetic ancestry testing.ConclusionsWhile these data are not used directly in matching for transplant, our results demonstrate that there is a place for the language of both race and geographic ancestry in the critical process of facilitating accurate prediction of HLA in the donor registry context.

Motivations for Direct-to-Consumer Genetic Testing: Understanding Interpretations of Ancestry Results

AbstractDirect-to-consumer genetic testing (DTCGT) has the potential to significantly impact racial and ethnic identities as well as social concepts of race and ethnicity. Prior literature challenges the binary choice of essentialism vs. constructionism in understanding consumers’ interpretations of genetic ancestry results. Largely focusing on differences by race and ethnicity, this research finds that test takers selectively apply genetically determinist logic depending on their prior identities and interests. We extend this line of inquiry using in-depth interviews with thirty-six mostly white participants who had previously taken a DTCGT offering combined health and ancestry results, which provided an opportunity to explore how different motivations for testing – e.g., for health or ancestry information – impact interpretations of ancestry results. Our analysis reveals distinct patterns in how health- vs. ancestry-motivated consumers invoke genetic determinism in their interpretations of DTCGT results. At the same time, regardless of motivation for testing, we found little use of genetic results to challenge the coherence or biological basis of racial or ethnic categories. Our results suggest that even if genetic determinism is only selectively applied, and in ways that vary between consumers with different motivations for testing, at least among whites, discourses of genetics as “truth” and white normativity are nonetheless the prevailing interpretive frameworks for genetic ancestry results.

DNA Identities: Narrative and Authority in Genetic Ancestry Performance on YouTube

Abstract The rise of direct-to-consumer genetic ancestry testing and social media technologies have converged to create a particular genre of vernacular identity performance: the genetic ancestry “reveal” on YouTube. This article seeks to understand these performances in relation to the authority that performers grant test results to inform racial and/or ethnic identities, how performers establish hierarchies of knowledge when family folklore and genetic test results collide, and what these performances reveal about conceptions of genetic determinism today.

Profiling genetically driven alternative splicing across the Indonesian archipelago.

One of the regulatory mechanisms influencing the functional capacity of genes is alternative splicing (AS). Previous studies exploring the splicing landscape of human tissues have shown that AS has contributed to human biology, especially in disease progression and the immune response. Nonetheless, this phenomenon remains poorly characterized across human populations, and it is unclear how genetic and environmental variation contribute to AS. Here, we examine a set of 115 Indonesian samples from three traditional island populations spanning the genetic ancestry cline that characterizes Island Southeast Asia. We conduct a global AS analysis between islands to ascertain the degree of functionally significant AS events and their consequences. Using an event-based statistical model, we detected over 1,500 significant differential AS events across all comparisons. Additionally, we identify over 6,000 genetic variants associated with changes in splicing (splicing quantitative trait loci [sQTLs]), some of which are driven by Papuan-like genetic ancestry, and only show partial overlap with other publicly available sQTL datasets derived from other populations. Computational predictions of RNA binding activity reveal that a fraction of these sQTLs directly modulate the binding propensity of proteins involved in the splicing regulation of immune genes. Overall, these results contribute toward elucidating the role of genetic variation in shaping gene regulation in one of the most diverse regions in the world.

Amplification of MYC and Its Enhancer Correlates With Genetic Ancestry in Lung Squamous Cell Carcinoma.

In lung squamous cell carcinoma (LUSC), Black patients show significantly higher incidence and lower overall survival than White patients. Although socioeconomic factors likely contribute to this survival disparity, genomic factors have yet to be elucidated in LUSC. Using 416 LUSC tumor samples in the Cancer Genome Atlas (TCGA), we assessed genomic and transcriptomic profiles by ancestry. We replicated our analyses in pan-cancer data from TCGA, the American Association of Cancer Research (AACR) Genomics Evidence Neoplasia Information Exchange (GENIE), and Columbia University Medical Center. We found increased MYC amplification, LUSC-specific MYC enhancer amplification, and chromosome arm 8q (chr8q) gain to be significantly associated with genetic AFR (African) ancestry in LUSC in TCGA. Furthermore, expression of MYC target genes was significantly enriched in AFR samples. Local ancestry analysis identified correlation of chr8q gain with AFR ancestry at the MYC locus in TCGA. We also found a significant correlation between chr8q and AFR ancestry in multiple cancer types and pan-cancer in TCGA. Similarly, in a pan-cancer subset of AACR GENIE data, we found a significant correlation between chr8q gain and race. Together, our data suggest that ancestry may influence amplification of not only MYC but also its enhancer in LUSC. They also suggest a role for genetic ancestry in chr8q aneuploidy in cancer. These studies further define and expand patients who may benefit from future anti-MYC therapeutic approaches.

Molecular correlates of social adversity in breast cancer.

48 Background: Neighborhood disadvantage (ND) is associated with shorter breast cancer (BCa) survival independent of individual, tumor, and treatment factors, suggesting more aggressive tumor biology in women from disadvantaged neighborhoods. This study evaluates how differential DNA methylation (DNAm), gene expression, and biologic pathways are wired with each other to delineate the regulatory landscape of ND on BCa. Methods: We leveraged 55 geocoded ER+/HER2- BCa samples from Hispanic White women enrolled in a prospective genomic-epidemiologic cohort study. Objective ND was evaluated using the Area Deprivation Index (ADI) and subjective ND was evaluated using the patient-reported Neighborhood Social Environment Adversity Survey and the Everyday Expanded Discrimination Survey. We analyzed the association between ND and (1) DNAm, (2) RNA transcription and miRNAs, and (3) blood concentration levels of DNAm co-factors (B12 and folate) from the same patient. To evaluate how the DNAm/expressed pathways are wired with each other to delineate the regulatory landscape of ND in these tumors, we performed correlation analyses among CpGs, genes, and miRNAs in the same topologically associated domain (TAD). We used Spearman correlation as our metric and adjusted the resulting p-values to FDR values. Results: The cohort was divided into low ND (ADI&lt;5; 31%) and a high ND (ADI&gt;=5; 69%). There were no significant differences between groups by age, race/ethnicity, genetic ancestry, BMI, smoking/alcohol, subtype, stage, or OncotypeDX scores. We discovered that high ND exhibits epigenetic deregulation of immune pathways, consistent with our findings of lower circulating B12 in high ND, suggesting activation of immune pathways through reduced systemic availability of methyl donors. RNA-seq identified higher tumor infiltration of immune cells in patients from high ND (e.g., Interferon alpha and gamma responses and inflammatory responses) consistent with aggressive biology. Estrogen response genes were downregulated suggesting that patients from high ND may develop estrogen-resistant tumors. Higher subjective ND scores discovered epigenetic changes on cell adhesion and calcium signaling genes, along with gene expression of E2F targets and cell cycle’s G2M checkpoint, indicative of a more proliferative/stemness signature. TAD analysis discovered significant developmental, immune, and signaling pathways when correlating DNAm with gene expression (e.g., estrogen response and EMT). Conclusions: In this multi-omic matched cohort, we discovered differentially methylated/expressed pathways, consistent with aggressive biology, wired with each other to identify a novel regulatory landscape of ND on BCa. These findings can inform interventions such as improved access to healthy nutrition (B12) in ND/food deserts or targeted stress-reduction interventions based on our survey findings to ultimately reverse aggressive tumor biology and reduce BCa disparities by ND.