Publications by authors named "Rasika A Mathias"

Brain structural volumes are highly heritable and are linked to multiple neuropsychological outcomes, including Alzheimer's disease (AD). Genome-wide association studies have successfully identified genetic variants associated with intracranial volume (ICV), total brain volume (TBV), hippocampal volume (HV), and lateral ventricular volume (LVV). However, these studies mostly focused on common genetic variants with minor allele frequencies (MAF) > 1%, and individuals included in most of these studies were of predominantly European ancestry.

View Article and Find Full Text PDF

Population descriptors used in genetic studies have broad social and translational implications. There are no globally agreed-upon definitions or usages of common population descriptors (e.g.

View Article and Find Full Text PDF

Accurate reconstruction of pedigrees from genetic data remains a challenging problem. Many relationship categories (e.g.

View Article and Find Full Text PDF

Background: von Willebrand disease (VWD) is a common inherited bleeding disorder caused by low levels or activity of circulating von Willebrand factor (VWF). Genetic susceptibility to VWF antigen (VWF:Ag) below normal (≤ 50 IU/dL) in the general population is underexplored.

Objectives: To identify genetic variants influencing VWF:Ag levels ≤ 50 IU/dL.

View Article and Find Full Text PDF

Increased cellular damage in aging tissues releases circulating cell-free genomic DNA (ccf-gDNA) into the bloodstream, and these fragments are associated with a higher risk of frailty and dementia. We hypothesized that identifying the tissue of origin for ccf-gDNA using methylation signatures can distinguish subgroups of participants with distinct clinical outcomes, biological aging rates, and energy use. Serum ccf-gDNA from 181 participants in the Religious Orders Study or Rush Memory and Aging Project (ROS-MAP) was assessed for DNA methylation at one timepoint using the Illumina MethylationEPIC array.

View Article and Find Full Text PDF

Polygenic risk score (PRS) prediction of complex diseases can be improved by leveraging related phenotypes. This has motivated the development of several multi-trait PRS methods that jointly model genetically correlated traits. However, these methods do not account for vertical pleiotropy, where one trait acts as a mediator for another.

View Article and Find Full Text PDF

Background: Genetic control of gene expression in asthma-related tissues is not well-characterized, particularly for African-ancestry populations, limiting advancement in our understanding of the increased prevalence and severity of asthma in those populations.

Objective: To create novel transcriptome prediction models for asthma tissues (nasal epithelium and CD4+ T cells) and apply them in transcriptome-wide association study (TWAS) to discover candidate asthma genes.

Methods: We developed and validated gene expression prediction databases for unstimulated CD4+ T cells (CD4+T) and nasal epithelium using an elastic net framework.

View Article and Find Full Text PDF

Background: Genome-wide association studies have identified several hundred susceptibility single nucleotide variants for coronary artery disease (CAD). Despite single nucleotide variant-based genome-wide association studies improving our understanding of the genetics of CAD, the contribution of structural variants (SVs) to the risk of CAD remains largely unclear.

Method And Results: We leveraged SVs detected from high-coverage whole genome sequencing data in a diverse group of participants from the National Heart Lung and Blood Institute's Trans-Omics for Precision Medicine program.

View Article and Find Full Text PDF

Large-scale whole-genome sequencing (WGS) studies have improved our understanding of the contributions of coding and noncoding rare variants to complex human traits. Leveraging association effect sizes across multiple traits in WGS rare variant association analysis can improve statistical power over single-trait analysis, and also detect pleiotropic genes and regions. Existing multi-trait methods have limited ability to perform rare variant analysis of large-scale WGS data.

View Article and Find Full Text PDF

Mosaic loss of Y (mLOY) is the most common somatic chromosomal alteration detected in human blood. The presence of mLOY is associated with altered blood cell counts and increased risk of Alzheimer disease, solid tumors, and other age-related diseases. We sought to gain a better understanding of genetic drivers and associated phenotypes of mLOY through analyses of whole-genome sequencing (WGS) of a large set of genetically diverse males from the Trans-Omics for Precision Medicine (TOPMed) program.

View Article and Find Full Text PDF

Clinical trials have shown favorable effects of exercise on frailty, supporting physical activity (PA) as a treatment and prevention strategy. Proteomics studies suggest that PA alters levels of many proteins, some of which may function as molecules in the biological processes underlying frailty. However, these studies have focused on structured exercise programs or cross-sectional PA-protein associations.

View Article and Find Full Text PDF

The following sections are included: Overview, Advancing multi-ancestry genetic research, Integrating social determinants of health to enhance genetic risk models, Methods to detect and mitigate disparities, Addressing Disparities in Adverse Drug Reactions, Conclusion, Acknowledgments,References.

View Article and Find Full Text PDF
Article Synopsis
  • Genetic studies have highlighted the need for more diverse research on plasma fibrinogen levels, as previous studies largely focused on Europeans, leading to gaps in understanding and missing heritability.
  • By analyzing data from whole-genome sequencing and genotype data from large cohorts, researchers identified 18 genetic loci related to fibrinogen levels, some of which are more common in African populations and include variants that may impact protein function.
  • The study's findings indicate a connection between fibrinogen levels and various health conditions, emphasizing the importance of whole-genome sequencing in discovering genetic factors in diverse populations and enhancing knowledge about fibrinogen regulation.
View Article and Find Full Text PDF

Physical frailty is a syndrome that typically manifests in later life, although the pathogenic process causing physical frailty likely begins decades earlier. To date, few studies have examined the biological signatures in mid-life associated with physical frailty later in life. Among 4,189 middle-aged participants (57.

View Article and Find Full Text PDF

Clonal hematopoiesis of indeterminate potential (CHIP), whereby somatic mutations in hematopoietic stem cells confer a selective advantage and drive clonal expansion, not only correlates with age but also confers increased risk of morbidity and mortality. Here, we leverage genetically predicted traits to identify factors that determine CHIP clonal expansion rate. We used the passenger-approximated clonal expansion rate method to quantify the clonal expansion rate for 4,370 individuals in the National Heart, Lung, and Blood Institute (NHLBI) Trans-Omics for Precision Medicine (TOPMed) cohort and calculated polygenic risk scores for DNA methylation aging, inflammation-related measures and circulating protein levels.

View Article and Find Full Text PDF
Article Synopsis
  • The study introduces endoPRS, a new weighted lasso model aimed at enhancing polygenic risk score (PRS) predictions for complex diseases by incorporating endophenotype data.
  • Unlike existing multi-trait PRS methods, endoPRS accounts for vertical pleiotropy, where one trait mediates the effects of another, without relying on specific genetic assumptions.
  • Simulation results and case studies, such as predicting childhood asthma risk using eosinophil count data from the UK Biobank, show that endoPRS significantly outperforms other PRS methods, highlighting its potential for improved clinical applications.
View Article and Find Full Text PDF
Article Synopsis
  • Coronary artery calcification (CAC) is linked to heart disease and assessed through a genome-wide association study (GWAS) involving 22,400 participants from various backgrounds.
  • The study confirmed connections with four known genetic loci and discovered two new loci related to CAC, with supportive replication findings for both.
  • Functional tests suggest that ARSE promotes calcification in vascular smooth muscle cells and its variants may influence CAC levels, identifying ARSE as a key target for potential treatments in vascular calcific diseases.
View Article and Find Full Text PDF
Article Synopsis
  • Asthma shows significant differences in prevalence and characteristics among various ancestral groups, yet the reasons for these disparities are not well understood.
  • The Consortium on Asthma among African-ancestry Populations in the Americas (CAAPA) is analyzing genetic information from individuals of African ancestry to identify specific genes related to asthma.
  • In their findings, they discovered 389 differentially expressed genes (DEGs), with key networks linked to immune response and wound healing, revealing three main areas of dysregulation important for understanding asthma within these populations.
View Article and Find Full Text PDF
Article Synopsis
  • Genome-wide association studies (GWAS) have successfully identified genes linked to telomere length, but previous research hadn't validated these findings until now.
  • In a large analysis involving over 211,000 people, the study discovered five new signals linked to telomere length and highlighted the importance of blood/immune cells in this area.
  • The researchers confirmed that the genes KBTBD6 and POP5 truly affect telomere length by demonstrating that manipulating these genes can lengthen telomeres and that their regulation is crucial for understanding telomere biology.
View Article and Find Full Text PDF
Article Synopsis
  • Inflammation biomarkers offer crucial insights into the inflammatory processes linked to various diseases, and their sequencing can help reveal the genetic makeup of these traits.
  • A study analyzed 21 inflammation biomarkers from around 38,465 individuals, discovering 22 significant associations across 6 inflammatory traits after considering existing findings.
  • The research combined single-variant and rare variant analyses, identifying additional significant associations and highlighting the complexity and diversity of genetic influences on inflammation traits across different ancestries.
View Article and Find Full Text PDF

Clonal hematopoiesis (CH) is characterized by the acquisition of a somatic mutation in a hematopoietic stem cell that results in a clonal expansion. These driver mutations can be single nucleotide variants in cancer driver genes or larger structural rearrangements called mosaic chromosomal alterations (mCAs). The factors that influence the variations in mCA fitness and ultimately result in different clonal expansion rates are not well understood.

View Article and Find Full Text PDF

Mosaic loss of Y (mLOY) is the most common somatic chromosomal alteration detected in human blood. The presence of mLOY is associated with altered blood cell counts and increased risk of Alzheimer's disease, solid tumors, and other age-related diseases. We sought to gain a better understanding of genetic drivers and associated phenotypes of mLOY through analyses of whole genome sequencing of a large set of genetically diverse males from the Trans-Omics for Precision Medicine (TOPMed) program.

View Article and Find Full Text PDF
Article Synopsis
  • * Discovery of 7 new genetic loci associated with FVIII and 1 new locus for VWF, supporting their roles in thrombotic outcomes via Mendelian randomization.
  • * Functional testing revealed that silencing genes like B3GNT2 and CD36 impacted FVIII and VWF release from endothelial cells, indicating their potential regulatory roles.
View Article and Find Full Text PDF

Polygenic risk scores (PRS) have shown successes in clinics, but most PRS methods focus only on participants with distinct primary continental ancestry without accommodating recently-admixed individuals with mosaic continental ancestry backgrounds for different segments of their genomes. Here, we develop GAUDI, a novel penalized-regression-based method specifically designed for admixed individuals. GAUDI explicitly models ancestry-differential effects while borrowing information across segments with shared ancestry in admixed genomes.

View Article and Find Full Text PDF