Esteban Parra

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Verified

Esteban verified their affiliation via an institutional email.

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• Ph.D.
• Professor (Full) at University of Toronto

Severe obesity (SevO) is a primary driver of cardiovascular diseases (CVD), cardiometabolic diseases (CMD) and several cancers, with a disproportionate impact on marginalized populations. SevO is an understudied global health disease, limiting knowledge about its mechanisms and impacts. In genome-wide association study (GWAS) meta-analyses of the t...

Background Age-related changes in DNA methylation (DNAm) play a critical role in regulating gene expression. However, most epigenome-wide association studies have predominantly focused on individuals of European descent. This study aims to characterize longitudinal changes in DNAm patterns in a cohort of elderly Brazilian participants. Methods DNA...

Modern humans and archaic hominins, namely Denisovans and Neanderthals, have been demonstrated to have a long history of admixture. Specifically, some of these admixture events have been adaptive and allowed modern humans to adapt to their new environments outside of Africa. Little research has been done on the impact of archaic introgression on ge...

The genetic basis of severe COVID-19 has been thoroughly studied, and many genetic risk factors shared between populations have been identified. However, reduced sample sizes from non-European groups have limited the discovery of population-specific common risk loci. In this second study nested in the SCOURGE consortium, we conducted a genome-wide...

The genetic basis of severe COVID-19 has been thoroughly studied, and many genetic risk factors shared between populations have been identified. However, reduced sample sizes from non-European groups have limited the discovery of population-specific common risk loci. In this second study nested in the SCOURGE consortium, we conducted a GWAS for COV...

Interbreeding between modern humans and archaic hominins, including Neanderthals and Denisovans, occurred as modern humans migrated outside of Africa. Here, we report on evidence of introgression from archaic hominins within genomic regions associated with circadian rhythm and chronotype using 76 worldwide modern human populations from the Human Ge...

The last couple of decades have highlighted the importance of studying hybridization, particularly among primate species, as it allows us to better understand our own evolutionary trajectory. Here, we report on genetic ancestry estimates using dense, full genome data from 881 olive (Papio anubus), yellow (Papio cynocephalus), or olive-yellow crosse...

We analyzed over 800 baboons using global and local ancestry genetic techniques and identified that over 10% of the labelled animals in the pedigree at the SNPRC baboon centre in San Antonio, Texas were mislabeled. Our results showcase the need for deeper understanding and genomic testing of pedigreed colonies to determine underlying cryptic past a...

Type 2 diabetes (T2D) is a heterogeneous disease that develops through diverse pathophysiological processes1,2 and molecular mechanisms that are often specific to cell type3,4. Here, to characterize the genetic contribution to these processes across ancestry groups, we aggregate genome-wide association study data from 2,535,601 individuals (39.7% n...

The genetic basis of severe COVID-19 has been thoroughly studied and many genetic risk factors shared between populations have been identified. However, reduced sample sizes from non-European groups have limited the discovery of population-specific common risk loci. In this second study nested in the SCOURGE consortium, we have conducted the larges...

The human subcortex is involved in memory and cognition. Structural and functional changes in subcortical regions is implicated in psychiatric conditions. We performed an association study of subcortical volumes using 15,941 tandem repeats (TRs) derived from whole exome sequencing (WES) data in 16,527 unrelated European ancestry participants. We id...

We examined through global and local ancestry genetics techniques over 800 captive baboons from the Southwest National Primate Research Centre in San Antonio, Texas. We identified that over 10% of the samples were incorrectly labelled at the species level due to cryptic admixture in the past. We also tested the validity of two different ancestry an...

Until January 2023, Brazil recorded 37 million COVID-19 cases despite the decrease in mortality due to mass vaccination efforts against COVID-19. The infection continues to challenge researchers and health professionals with the persistent symptoms and onset manifestations after the acute phase of the disease, namely Post-Covid Condition (PCC). Bei...

Critical illness in COVID-19 is an extreme and clinically homogeneous disease phenotype that we have previously shown1 to be highly efficient for discovery of genetic associations2. Despite the advanced stage of illness at presentation, we have shown that host genetics in patients who are critically ill with COVID-19 can identify immunomodulatory t...

There is increasing evidence that the complexity of the retinal vasculature measured as fractal dimension, Df, might offer earlier insights into the progression of coronary artery disease (CAD) before traditional biomarkers can be detected. This association could be partly explained by a common genetic basis; however, the genetic component of Df is...

Introduction: Research in the field of pharmacogenomics (PGx) aims to identify genetic variants that modulate response to drugs, through alterations in their pharmacokinetics (PK) or pharmacodynamics (PD). The distribution of PGx variants differs considerably among populations, and whole-genome sequencing (WGS) plays a major role as a comprehensive...

Until January 2023, Brazil recorded 37 million COVID-19 cases despite the decrease in mortality after mass vaccination efforts for SARS-CoV-2. The infection continues to challenge researchers and health professionals with persistent symptoms and onset manifestations after the acute phase of the disease, namely Post-Covid Condition (PCC). Being one...

Type 2 diabetes (T2D) is a heterogeneous disease that develops through diverse pathophysiological processes. To characterise the genetic contribution to these processes across ancestry groups, we aggregate genome-wide association study (GWAS) data from 2,535,601 individuals (39.7% non-European ancestry), including 428,452 T2D cases. We identify 1,2...

Background: The Infinium EPIC array measures the methylation status of > 850,000 CpG sites. The EPIC BeadChip uses a two‐array design: Infinium Type I and Type II probes. These probe types exhibit different technical characteris‐ tics which may confound analyses. Numerous normalization and pre‐processing methods have been developed to reduce probe...

[This corrects the article DOI: 10.1016/j.xhgg.2022.100099.].

Background Genetic variants within nearly 1000 loci are known to contribute to modulation of blood lipid levels. However, the biological pathways underlying these associations are frequently unknown, limiting understanding of these findings and hindering downstream translational efforts such as drug target discovery. Results To expand our understa...

Common single-nucleotide polymorphisms (SNPs) are predicted to collectively explain 40–50% of phenotypic variation in human height, but identifying the specific variants and associated regions requires huge sample sizes¹. Here, using data from a genome-wide association study of 5.4 million individuals of diverse ancestries, we show that 12,111 inde...

In this study, we present the results of a genome-wide scan for signatures of positive selection using data from four tribal groups (Kokana, Warli, Bhil, and Pawara) and two caste groups (Deshastha Brahmin and Kunbi Maratha) from West of the Maharashtra State In India, as well as two samples of South Asian ancestry from the 1KG project (Gujarati In...

A major challenge of genome-wide association studies (GWASs) is to translate phenotypic associations into biological insights. Here, we integrate a large GWAS on blood lipids involving 1.6 million individuals from five ancestries with a wide array of functional genomic datasets to discover regulatory mechanisms underlying lipid associations. We fir...

We assembled an ancestrally diverse collection of genome-wide association studies (GWAS) of type 2 diabetes (T2D) in 180,834 affected individuals and 1,159,055 controls (48.9% non-European descent) through the Diabetes Meta-Analysis of Trans-Ethnic association studies (DIAMANTE) Consortium. Multi-ancestry GWAS meta-analysis identified 237 loci atta...

Eye colour is highly variable in populations with European ancestry, ranging from low to high quantities of melanin in the iris. Polymorphisms in the HERC2/OCA2 locus have the largest effect on eye colour in these populations, although other genomic regions also influence eye colour. We performed genome-wide association studies of eye colour in a C...

Hispanic/Latinos have been underrepresented in genome-wide association studies (GWAS) for anthropometric traits despite their notable anthropometric variability, ancestry proportions, and high burden of growth stunting and overweight/obesity. To address this knowledge gap, we analyzed densely-imputed genetic data in a sample of Hispanic/Latino adul...

Genetic variants within nearly 1,000 loci are known to contribute to modulation of blood lipid levels. However, the biological pathways underlying these associations are frequently unknown, limiting understanding of these findings and hindering downstream translational efforts such as drug target discovery. To expand our understanding of the underl...

There is increasing evidence that the complexity of the retinal vasculature (measured as fractal dimension, Df) might offer earlier insights into the progression of coronary artery disease (CAD) before traditional biomarkers can be detected. This association could be partly explained by a common genetic basis; however, the genetic component of Df i...

Increased blood lipid levels are heritable risk factors of cardiovascular disease with varied prevalence worldwide owing to different dietary patterns and medication use¹. Despite advances in prevention and treatment, in particular through reducing low-density lipoprotein cholesterol levels², heart disease remains the leading cause of death worldwi...

A major challenge of genome-wide association studies (GWAS) is to translate phenotypic associations into biological insights. Here, we integrate a large GWAS on blood lipids involving 1.6 million individuals from five ancestries with a wide array of functional genomic datasets to discover regulatory mechanisms underlying lipid associations. We firs...

Hair colour is a polygenic phenotype that results from differences in the amount and ratio of melanins located in the hair bulb. Genome-wide association studies (GWAS) have identified many loci involved in the pigmentation pathway affecting hair colour. However, most of the associated loci overlap non-protein coding regions and many of the molecula...

The main factors that determine eye colour are the amount of melanin concentrated in iris melanocytes, as well as the shape and distribution of melanosomes. Eye colour is highly variable in populations with European ancestry, in which eye colour categories cover a continuum of low to high quantities of melanin accumulated in the iris. A few polymor...

Central obesity is a leading health concern with a great burden carried by ethnic minority populations, especially Hispanics/Latinos. Genetic factors contribute to the obesity burden overall and to inter-population differences. We aimed to identify loci associated with central adiposity measured as waist-to-hip ratio (WHR), waist circumference (WC)...

Hispanic/Latinos have been underrepresented in genome-wide association studies (GWAS) for anthropometric traits despite notable anthropometric variability with ancestry proportions, and a high burden of growth stunting and overweight/obesity in Hispanic/Latino populations. This address this knowledge gap, we analyzed densely-imputed genetic data in...

Central obesity is a leading health concern with a great burden carried by ethnic minority populations, and especially Hispanics/Latinos. Genetic factors contribute to the obesity burden overall and to inter-population differences. We aim to: 1) identify novel loci associated with central adiposity measured as waist-to-hip ratio (WHR), waist circum...

We evaluated the performance of three PGx panels to estimate biogeographical ancestry: the DMET panel, and the VIP and Preemptive PGx panels described in the literature. Our analysis indicate that the three panels capture quite well the individual variation in admixture proportions observed in recently admixed populations throughout the Americas, w...

We assembled an ancestrally diverse collection of genome-wide association studies of type 2 diabetes (T2D) in 180,834 cases and 1,159,055 controls (48.9% non-European descent). We identified 277 loci at genome-wide significance (p<5x10-8), including 237 attaining a more stringent trans-ancestry threshold (p<5x10-9), which were delineated to 338 dis...

The South Asian subcontinent is characterized by a complex history of human migrations and population interactions. In this study, we used genome-wide data to provide novel insights on the demographic history and population relationships of six Indo-European populations from the Indian State of West Maharashtra. The samples correspond to two castes...

Over the past few years, tools capable of predicting pigmentation phenotypes have been developed aiming to contribute for criminal and anthropological investigations. In this study, we used eight genetic systems to infer eye, hair, and skin color of ancient and contemporary Native Americans. To achieve this goal, we retrieved 61 SNPs from 42 sample...

Genome-wide association studies (GWASs) have identified many genetic variations associated with type 2 diabetes mellitus (T2DM) in Asians, but understanding the functional genetic variants that influence traits is often a complex process. In this study, fine mapping and other analytical strategies were performed to investigate the effects of G prot...

Background: Association studies in recently admixed populations are extremely useful to identify the genetic architecture of pigmentation, due to their high genotypic and phenotypic variation. However, to date only four Genome-Wide Association Studies (GWAS) have been carried out in these populations. Results: We present a GWAS of skin pigmentat...

The main goal of DNA phenotyping is to predict externally visible characteristics (EVCs) of an individual using only its genetic information. Nowadays, the HIrisPlex-S system stands as a reliable model designed for skin color prediction. However, prediction of skin color phenotypes has not been thoroughly tested in recently admixed populations, so...

Recently, studies have shown significant association between the rs2000999 polymorphism in the haptoglobin-encoding gene (HP) and low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC) levels, which are important risk factors for cardiovascular diseases. However, the association of rs2000999 with serum lipids in Latin American diabe...

Although hundreds of GWAS-implicated loci have been reported for adult obesity-related traits, less is known about the genetics specific for early-onset obesity, and with only a few studies conducted in non-European populations to date. Searching for additional genetic variants associated with childhood obesity, we performed a trans-ancestral meta-...

South Asia has a complex history of migrations, and is characterized by substantial pigmentary and genetic diversity. For this reason, it is an ideal region to study the genetic architecture of normal pigmentation variation. Here, we present a meta-analysis of two GWAS of skin pigmentation using skin reflectance (M-index) as a quantitative phenotyp...

SNP analysis is of paramount importance in forensic genetics. The development of new technologies in next-generation sequencing allowed processing a large number of markers in various samples simultaneously. Although SNPs are less informative than STRs, they present lower mutation rates and perform better when using degraded samples. Some SNP syste...

Interpretation of genetic association results is difficult because signals often lack biological context. To generate hypotheses of the functional genetic etiology of complex cardiometabolic traits, we estimated the genetically determined component of gene expression from common variants using PrediXcan (1) and determined genes with differential pr...

Chronic kidney disease (CKD) affects ~10% of the global population, with considerable ethnic differences in prevalence and aetiology. We assemble genome-wide association studies of estimated glomerular filtration rate (eGFR), a measure of kidney function that defines CKD, in 312,468 individuals of diverse ancestry. We identify 127 distinct associat...

Background/objectives: Mexico has one of the highest prevalence of childhood obesity in the world. Genome-wide association studies (GWAS) for obesity have identified multiple single-nucleotide polymorphisms (SNPs) in populations of European, East Asian, and African descent. The contribution of these loci to obesity in Mexican children is unclear....

Like many highly variable human traits, more than a dozen genes are known to contribute to the full range of skin color. However, the historical bias in favor of genetic studies in European and European‐derived populations has blinded us to the magnitude of pigmentation's complexity. As deliberate efforts are being made to better characterize diver...

Background Genome-wide association studies have implicated the transcription factor 7-like 2 (TCF7L2) gene in type 2 diabetes risk, and more recently, in decreased body mass index. Given the contrary direction of genetic effects on these two traits, it has been suggested that the observed association with body mass index may reflect either selectio...

Chronic kidney disease (CKD) affects ~10% of the global population, with considerable ethnic differences in prevalence and aetiology. We assembled genome-wide association studies (GWAS) of estimated glomerular filtration rate (eGFR), a measure of kidney function that defines CKD, in 312,468 individuals from four ancestry groups. We identified 93 lo...

Cuba is the most populated country in the Caribbean and has a rich and heterogeneous genetic heritage. Here, we take advantage of dense genomic data from 860 Cuban individuals to reconstruct the genetic structure and ancestral origins of this population. We found distinct admixture patterns between and within the Cuban provinces. Eastern provinces...

Pharmacogenetics/pharmacogenomics (PGx) relies on human genetic diversity. In this review we initially examine the PGx implications of human demographic history and genetic diversity, and highlight results from recent studies on the worldwide distribution of common and rare variants in pharmacogenes. The abundance of rare variants implies that a su...

The effect of Copy Number Variants (CNVs) on Type 2 Diabetes (T2D) remains little explored. The present study characterized large rare CNVs in 686 T2D and 194 non-T2D subjects of Mexican ancestry genotyped using the Affymetrix Genome-Wide Human SNP array 5.0. Rare CNVs with ≥ 100 kb length were identified using a stringent strategy based on merging...

Background Currently, there is limited knowledge about the genetics underlying pigmentary traits in East Asian populations. Here, we report the results of the first genome-wide association study of pigmentary traits (skin and iris color) in individuals of East Asian ancestry. Methods We obtained quantitative skin pigmentation measures (M-index) in...

Distribution of skin pigmentation, expressed as M-index values, in the East Asian sample

Genome-wide significant and suggestive signals observed in the genome-wide association study of skin pigmentation (M-index) and iris color (L*, a*, b* and delta values) All the regions indicated in the file have more than one genome-wide significant or suggestive marker with good imputation scores (info score >0.8).

Regional plots for suggestive regions (p-value <10−5) identified in the GWAs of iris color (L* values) All these regions harbour multiple markers showing suggestive significance and good imputation.

Regional plots for suggestive regions (p-value <10−5) identified in the GWAs of iris color (a* values) All these regions harbour multiple markers showing suggestive significance and good imputation scores (e.g., score info > 0.8).

Table reporting allele frequencies and effect size estimates in the East Asian sample for markers known to be associated with light skin in European populations The table includes variants in the genes SLC24A5 and SLC45A2, which have very high frequencies in Europe and have been reported to have very strong effects on skin pigmentation in admixed g...

Distribution of delta values (e.g., difference in color coordinates between the pupillary and ciliary regions of the iris) in the East Asian sample

Regional plots for suggestive regions (p-value <10−5) identified in the GWAs of skin pigmentation All these regions harbour multiple markers showing suggestive significance and good imputation scores (e.g., score info > 0.8).

QQ plots for L*, a* and b* iris color coordinates and delta values

Regional plots for suggestive regions (p-value <10−5) identified in the GWAs of iris color (delta values) All these regions harbour multiple markers showing suggestive significance and good imputation scores (e.g., score info > 0.8).

Scatterplots of a* and b* ( Fig. 2A), a* and L* (Fig. 2B) and b* and L* (Fig. 2C) CIELab iris color coordinates in the East Asian sample

Principal Component Analysis (PCA) coordinates (axes 1 and 2) of the East Asian sample analyzed in the study, as well as the East Asian samples of the 1000 Genomes Project CDX, Chinese Dai in Xishuangbanna, KHV, Kinh in Ho Chi Minh City, Vietnam, CHB, Han Chinese in Beijing, CHS, Han Chinese South and JPT, Japanese in Tokyo.

QQ plot for skin pigmentation

Regional plots for suggestive regions (p-value <10−5) identified in the GWAs of iris color (b* values) All these regions harbour multiple markers showing suggestive significance and good imputation scores (e.g., score info > 0.8).

Background Despite ethnic disparities in lipid profiles, there are few genome-wide association studies investigating genetic variation of lipids in non-European ancestry populations. In this study, we present findings from genetic association analyses for total cholesterol, low density lipoprotein cholesterol (LDL), high density lipoprotein cholest...

Objective: Mexico's current population structure has been defined by admixture between European, Native American, and to some extent African, groups that started in the sixteenth century. The aim of this research was to analyze the relative contributions of these continental population groups to the seven regions of the state of Guerrero, Mexico....

The evidence for a relationship of vitamin D with non-skeletal health outcomes is inconsistent. The validity of single or predicted measurements of 25-hydroxyvitamin D (25(OH)D) is unknown as this biomarker is highly seasonally variable. We compared models of 25(OH)D at baseline, at multiple time points throughout the year, and averaged over the ye...

Childhood obesity is a global health concern due to its potential to increase cardiometabolic risk across the life course. In the United States (US) the burden of childhood obesity is highest among Hispanic/Latinos, in particular children or adolescents of Mexican descent. Although the genetic epidemiology of childhood obesity has been studied prev...

We carried out an admixture mapping study of lipid traits in two samples from Mexico City. Native American locus ancestry was significantly associated with triglyceride levels in a broad region of chromosome 11 overlapping the BUD13, ZNF259 and APOA5 genes. In our fine-mapping analysis of this region using dense genome-wide data, rs964184 is the on...

Principal Component Analysis (PCA) of the Mexican samples used in the admixture mapping analysis and relevant parental populations samples. (TIF)

P-values obtained in TG GWA study for markers in the BUD13/ZNF259/APOA5 region with and without conditioning for rs964184. (XLSX)

Supporting Information S1