Biomedical subjects

Pradeep Natarajan

Publications and source records attributed to Pradeep Natarajan.

26 records · Page 2Linked to original sources

PubMed2025

DiscoDivas: Leveraging genetic ancestry continuum information to interpolate PRS for admixed populations.

The relatively low representation of admixed populations in both discovery and fine-tuning individual-level datasets limits polygenic risk score (PRS) development and equitable clinical translation for admixed populations. Under the assumption that the most informative PRS model for a genetically homogeneous sample varies linearly in an ancestry continuum space, we introduce a Genetic Distance-assisted PRS Combination Pipeline for Diverse Genetic Ancestries (DiscoDivas) to interpolate a harmonized PRS for diverse, especially admixed, genetic ancestries, leveraging multiple PRS models fine-tuned within existing samples, which are mostly of single ancestry, and genetic distance. DiscoDivas treats genetic ancestry as a continuous variable and does not require shifting between different models when calculating PRS for different ancestries. We generated PRS with DiscoDivas and the current conventional method, i.e. fine-tuning multiple GWAS PRS using the matched or similar genetic ancestry samples. DiscoDivas generated a harmonized PRS of the accuracy comparable to or higher than the conventional approach, with the greatest advantage exhibited in admixed individuals.

PRS harmonization↗

PubMed2025

Polygenic Prediction of Peripheral Artery Disease and Major Adverse Limb Events.

IMPORTANCE: Peripheral artery disease (PAD) is a heritable atherosclerotic condition associated with functional decline and high risk for limb loss. With growing knowledge of the genetic basis for PAD and related risk factors, there is potential opportunity to identify individuals at high risk using polygenic risk scores (PRSs). OBJECTIVE: To develop a novel integrated, multiancestry polygenic score for PAD (PRS-PAD) and evaluate its risk estimation for PAD and major adverse limb events in 3 populations. DESIGN, SETTING, AND PARTICIPANTS: This longitudinal cohort study was conducted among individuals with genotyping and electronic health record data in the UK Biobank (2006-2021), All of Us (AoU, 2018-2022), and the Mass General Brigham Biobank (MGBB, 2010-2023). Data were analyzed from July 2023 to February 2025. EXPOSURES: PRS-PAD, previously published PAD polygenic scores, and clinical risk factors. MAIN OUTCOMES AND MEASURES: The primary outcomes were PAD and major adverse limb events, defined as a surrogate of major amputation and acute limb ischemia. RESULTS: The study populations included 400 533 individuals from the UK Biobank (median [IQR] age, 58.2 [45.0-71.4] years; 216 215 female participants [53.9%]), 218 500 from AoU (median [IQR] age, 53.6 [37.7-65.0] years; 132 647 female participants [60.7%]), and 32 982 from MGBB (median [IQR] age, 56.0 [32.0-80.0] years; 18 277 female participants [55.4%]). In the UK Biobank validation cohort, PRS-PAD was associated with an odds ratio [OR] per SD increase of 1.63 (95% CI, 1.60-1.68; P < .001). After adjusting for clinical risk factors, the OR for the top 20% of PRS-PAD was 1.68 (95% CI, 1.62-1.74; P < .001) compared to the remainder of the population. Among PAD cases without a history of diabetes, smoking, or chronic kidney disease (n = 3645), 1097 individuals (30.1%) had a high PRS-PAD (top 20%). In incident disease analysis, PRS-PAD improved discrimination (C statistic, 0.761), which was nearly equivalent to the performances of diabetes (C statistic, 0.760) and smoking (C statistic, 0.765). Among individuals with prevalent PAD, high PRS-PAD was associated with an increased risk of incident major adverse limb events in the UK Biobank (hazard ratio [HR], 1.75; 95% CI, 1.18-2.57; P = .005), MGBB (HR, 1.56; 95% CI, 1.06-2.30; P = .02), and AoU (HR, 1.57; 95% CI, 1.06-2.33; P = .03). CONCLUSIONS AND RELEVANCE: This cohort study develops a new PRS that stratifies risk of PAD and adverse limb outcomes. Incorporating polygenic risk into PAD care warrants further investigation to guide screening and tailor management to prevent major adverse limb events.

Humans↗

PubMed2025

Robust pleiotropy-decomposed polygenic scores identify distinct contributions to elevated coronary artery disease polygenic risk.

BACKGROUND: Polygenic risk score (PRS) have proved to offer robust risk prediction for coronary artery disease (CAD). However, the global CAD PRS summarizes the joint effects of all the markers in the genome, masking potential genetic heterogeneity that may be important for disease interpretation and targeted interventions. METHODS: Using summary-level data, we identified 43 significant CAD-related traits based on genetic correlations, and further classified them into eight pleiotropy clusters based on their biological functions. We then partitioned the genome into 2,353 near-independent regions. Variants in each region were assigned to the trait most genetically similar to CAD, and then were labeled with the corresponding pleiotropy cluster. We grouped variants without labels into a ninth, non-specific cluster. The Pleiotropy Decomposed (PD) PRSs for each of the nine clusters were calculated using variants assigned to each cluster for 407,903 samples of European ancestry from the UK Biobank (UKBB). RESULTS: We decomposed the CAD PRS into nine PD-PRSs and further stratified individuals with high CAD-PRS into nine subgroups. Each PD-PRS accounted for a higher proportion of the global CAD-PRS within its corresponding subgroup than in the remaining subjects with high CAD-PRS (e.g., 25.2% (0.07) vs. 10.06% (0.07) for lipids-PD-PRS). Additionally, these subgroups showed distinct clinical features. For example, in the lipids-related subgroup, lipoprotein(a) and LDL-cholesterol levels were 67.5% and 18.3% higher, respectively, compared to the remaining high-risk individuals. Furthermore, significant interactions were observed between blood pressure and BP PD-PRS, and between current smoking and respiratory system PD-PRS. CONCLUSION: Our findings suggest that PD-PRSs may reveal substantial genetic and phenotypic heterogeneity among individuals with high CAD-PRS. The unique PD-PRS compositions of each individual can highlight the relative importance of different pleiotropic regions.

Humans↗

PubMed2025

Nonadherence to guidelines for genetic testing in families with ovarian cancer shows racial bias.

PURPOSE: The National Comprehensive Cancer Network (NCCN) recommends germline genetic testing for individuals at risk for hereditary ovarian cancer. We sought to determine the proportion and characteristics of individuals meeting testing criteria in a multicenter biobank who were appropriately offered testing. METHODS: In this retrospective cohort study, we identified Mass General Brigham Biobank participants meeting genetic testing criteria per NCCN guidelines. Logistic regression was used to analyze sociodemographic factors associated with which participants were offered testing, completed testing, and had a family history that matched their self-report documented in the electronic medical record. RESULTS: Most eligible participants (909/1441, 63.1%) were not offered genetic testing. Participants who were Black or Hispanic had a lower likelihood of being offered testing. Compared with self-report, 988 (68.6%) participants had a family history of ovarian cancer documented in their electronic medical record. Older age, Hispanic ethnicity, and public insurance use were associated with decreased likelihoods of accurate family history documentation. Correct documentation was associated with an increased likelihood of being offered testing. CONCLUSION: The majority of participants in this study did not receive NCCN-compliant care. Germline genetic testing for hereditary ovarian cancer screening is underutilized and access to this testing is currently inequitable.

Adult↗

PubMed2025

Deciphering Clonal Hematopoiesis of Indeterminate Potential: Methods, Mechanisms, and Implications for Kidney Diseases.

CKD afflicts over 10% of US adults, with its prevalence increasing sharply with age. Clonal hematopoiesis of indeterminate potential (CHIP) is a common, genetically heterogeneous blood cell disorder characterized by the age-related clonal expansion of hematopoietic cells driven by leukemogenic somatic mutations yet without hematologic malignancy or dysplasia. While CHIP is a strong risk factor of future hematologic malignancy (estimated at approximately 0.5% per year, compared with <0.1% for those without CHIP), it is also linked to two-fold higher cardiovascular disease in epidemiologic, cell-based, and murine studies. However, more recent work has implicated CHIP with kidney outcomes, such as CKD as well as AKI, independent of traditional risk factors. This review covers the observations and proposed hypotheses linking CHIP and kidney disease. The review also underscores the need for further research to elucidate the distinct pathways through which CHIP may contribute to CKD and its comorbidities, considering the heterogeneity within CKD stages and etiologies, as well as whether CHIP is a causal driver of kidney disease or a marker of aging and comorbidity. Finally, we discuss the potential of anti-inflammatory treatments to mitigate CHIP's adverse effects on kidney health, aiming to improve management strategies for patients with CHIP-associated kidney diseases.

Humans↗

PubMed2025

Genetic Predisposition to Low-Density Lipoprotein Cholesterol and Incident Type 2 Diabetes.

IMPORTANCE: Treatment to lower high levels of low-density lipoprotein cholesterol (LDL-C) reduces incident coronary artery disease (CAD) risk but modestly increases the risk for incident type 2 diabetes (T2D). The extent to which genetic factors across the cholesterol spectrum are associated with incident T2D is not well understood. OBJECTIVE: To investigate the association of genetic predisposition to increased LDL-C levels with incident T2D risk. DESIGN, SETTING, AND PARTICIPANTS: In this large prospective, population-based cohort study, UK Biobank participants who underwent whole-exome sequencing and genome-wide genotyping were included. Participants were separated into 7 groups with familial hypercholesterolemia (FH), predicted loss of function (pLOF) in APOB or PCSK9 variants, and LDL-C polygenic risk score (PRS) quintiles. Data were collected between 2006 and 2010, with a median follow-up of 13.7 (IQR, 12.9-14.5) years. Data were analyzed from March 1 to November 1, 2024. EXPOSURES: LDL-C level, LDL-C PRS, FH, or pLOF variant status. MAIN OUTCOMES AND MEASURES: Cox proportional hazards regression models adjusted for age, sex, genotyping array, lipid-lowering medication use, and the first 10 genetic principal components were fitted to assess the association between LDL-C genetic factors and incident T2D and CAD risks. RESULTS: Among the 361 082 participants, mean (SD) age was 56.8 (8.0) years, 194 751 (53.9%) were female, and mean (SD) baseline LDL-C level was 138.0 (33.6) mg/dL. During the follow-up period, 22 619 (6.3%) participants developed incident T2D and 17 966 (5.0%) developed incident CAD. The hazard ratio for incident T2D was lowest in the FH group (0.65; 95% CI, 0.54-0.77), while the highest risk was in the pLOF group (1.48; 95% CI, 1.18-1.86). The association between LDL-C PRS and incident T2D was 0.72 (95% CI, 0.66-0.79) for very high LDL-C PRS, 0.87 (95% CI, 0.84-0.90) for high LDL-C PRS, 1.13 (95% CI, 1.09-1.17) for low LDL-C PRS, and 1.26 (95% CI, 1.15-1.38) for very low LDL-C PRS. CAD risk increased directly with the LDL-C PRS. CONCLUSIONS AND RELEVANCE: In this cohort study, LDL-C and T2D risks were inversely associated across genetic mechanisms for LDL-C variation. Further elucidation of the mechanisms associating low LDL-C risk with increased risk of T2D is warranted.

Humans↗

PubMed2025

Distinct Genetic Risk Profile in Aortic Stenosis Compared With Coronary Artery Disease.

IMPORTANCE: Aortic stenosis (AS) and coronary artery disease (CAD) frequently coexist. However, it is unknown which genetic and cardiovascular risk factors might be AS-specific and which could be shared between AS and CAD. OBJECTIVE: To identify genetic risk loci and cardiovascular risk factors with AS-specific associations. DESIGN, SETTING, AND PARTICIPANTS: This was a genomewide association study (GWAS) of AS adjusted for CAD with participants from the European Consortium for the Genetics of Aortic Stenosis (EGAS) (recruited 2000-2020), UK Biobank (recruited 2006-2010), Estonian Biobank (recruited 1997-2019), and FinnGen (recruited 1964-2019). EGAS participants were collected from 7 sites across Europe. All participants were of European ancestry, and information on comorbid CAD was available for all participants. Follow-up analyses with GWAS data on cardiovascular traits and tissue transcriptome data were also performed. Data were analyzed from October 2022 to July 2023. EXPOSURES: Genetic variants. MAIN OUTCOMES AND MEASURES: Cardiovascular traits associated with AS adjusted for CAD. Replication was performed in 2 independent AS GWAS cohorts. RESULTS: A total of 18 792 participants with AS and 434 249 control participants were included in this GWAS adjusted for CAD. The analysis found 17 AS risk loci, including 5 loci with novel and independently replicated associations (RNF114A, AFAP1, PDGFRA, ADAMTS7, HAO1). Of all 17 associated loci, 11 were associated with risk specifically for AS and were not associated with CAD (ALPL, PALMD, PRRX1, RNF144A, MECOM, AFAP1, PDGFRA, IL6, TPCN2, NLRP6, HAO1). Concordantly, this study revealed only a moderate genetic correlation of 0.15 (SE, 0.05) between AS and CAD (P = 1.60 × 10-3). Mendelian randomization revealed that serum phosphate was an AS-specific risk factor that was absent in CAD (AS: odds ratio [OR], 1.20; 95% CI, 1.11-1.31; P = 1.27 × 10-5; CAD: OR, 0.97; 95% CI 0.94-1.00; P = .04). Mendelian randomization also found that blood pressure, body mass index, and cholesterol metabolism had substantially lesser associations with AS compared with CAD. Pathway and transcriptome enrichment analyses revealed biological processes and tissues relevant for AS development. CONCLUSIONS AND RELEVANCE: This GWAS adjusted for CAD found a distinct genetic risk profile for AS at the single-marker and polygenic level. These findings provide new targets for future AS research.

Humans↗

PubMed2024

The Genetic Determinants and Genomic Consequences of Non-Leukemogenic Somatic Point Mutations.

Clonal hematopoiesis (CH) is defined by the expansion of a lineage of genetically identical cells in blood. Genetic lesions that confer a fitness advantage, such as point mutations or mosaic chromosomal alterations (mCAs) in genes associated with hematologic malignancy, are frequent mediators of CH. However, recent analyses of both single cell-derived colonies of hematopoietic cells and population sequencing cohorts have revealed CH frequently occurs in the absence of known driver genetic lesions. To characterize CH without known driver genetic lesions, we used 51,399 deeply sequenced whole genomes from the NHLBI TOPMed sequencing initiative to perform simultaneous germline and somatic mutation analyses among individuals without leukemogenic point mutations (LPM), which we term CH-LPMneg. We quantified CH by estimating the total mutation burden. Because estimating somatic mutation burden without a paired-tissue sample is challenging, we developed a novel statistical method, the Genomic and Epigenomic informed Mutation (GEM) rate, that uses external genomic and epigenomic data sources to distinguish artifactual signals from true somatic mutations. We performed a genome-wide association study of GEM to discover the germline determinants of CH-LPMneg. After fine-mapping and variant-to-gene analyses, we identified seven genes associated with CH-LPMneg (TCL1A, TERT, SMC4, NRIP1, PRDM16, MSRA, SCARB1), and one locus associated with a sex-associated mutation pathway (SRGAP2C). We performed a secondary analysis excluding individuals with mCAs, finding that the genetic architecture was largely unaffected by their inclusion. Functional analyses of SMC4 and NRIP1 implicated altered HSC self-renewal and proliferation as the primary mediator of mutation burden in blood. We then performed comprehensive multi-tissue transcriptomic analyses, finding that the expression levels of 404 genes are associated with GEM. Finally, we performed phenotypic association meta-analyses across four cohorts, finding that GEM is associated with increased white blood cell count and increased risk for incident peripheral artery disease, but is not significantly associated with incident stroke or coronary disease events. Overall, we develop GEM for quantifying mutation burden from WGS without a paired-tissue sample and use GEM to discover the genetic, genomic, and phenotypic correlates of CH-LPMneg.

Journal Article↗