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Biology subjects

Kumar, R.

Publications and source records attributed to Kumar, R..

At least 19 recordsLinked to original sources

Mouse REC114 is essential for meiotic DNA double-strand break formation and forms a complex with MEI4

Programmed formation of DNA double strand breaks (DSBs) initiates the meiotic homologous recombination pathway. This pathway allows homologous chromosomes to find each other and the formation of crossing overs, the products of reciprocal exchanges, which are required for proper chromosome segregation at the first meiotic division. Meiotic DSBs are catalyzed by Spo11 that forms a complex with a second subunit, TopoVIBL, and mediates a DNA type II topoisomerase-like cleavage. Several other proteins are essential for meiotic DSB formation, including three evolutionarily conserved proteins first identified in Saccharomyces cerevisiae (Mer2, Mei4 and Rec114). These three S. cerevisiae proteins and their mouse orthologs (IHO1, MEI4 and REC114) co-localize on the axes of meiotic chromosomes, and mouse IHO1 and MEI4 are essential for meiotic DSB formation. Here, we show that mouse Rec114 is required for meiotic DSB formation. Moreover, MEI4 forms a complex with REC114 and IHO1 in mouse spermatocytes, consistent with cytological observations. We then demonstrated in vitro the formation of a stable complex between REC114 C-terminal domain and MEI4 N-terminal domain. We further determine the structure of REC114 N-terminal domain that revealed similarity with Pleckstrin Homology domains and its property to dimerize. These analyses provide direct insights into the architecture of these essential components of the meiotic DSB machinery.

molecular biology

Translational initiation factor eIF5 replaces eIF1 on the 40S ribosomal subunit to promote start-codon recognition

In eukaryotic translation initiation AUG recognition of the mRNA requires accommodation of Met-tRNAi in a \"PIN\" state, which is antagonized by the factor eIF1. eIF5 is a GTPase activating protein (GAP) of eIF2 that additionally promotes stringent AUG selection, but the molecular basis of its dual function was unknown. We present a cryo-electron microscopy (cryo-EM) reconstruction of a 48S pre-initiation complex (PIC), at an overall resolution of 3.0 [A], featuring the N-terminal domain (NTD) of eIF5 bound to the 40S subunit at the location vacated by eIF1. eIF5 interacts with and allows a more accommodated orientation of Met-tRNAi. Substitutions of eIF5 residues involved in the eIF5-NTD/tRNAi interaction influenced initiation at near-cognate UUG codons in vivo, and the closed/open PIC conformation in vitro, consistent with direct stabilization of the codon:anticodon duplex by the wild-type eIF5-NTD. The present structure reveals the basis for a key role of eIF5 in start-codon selection.

biophysics

Investigating the long-term stability of protein immunogen(s) for whole recombinant yeast-based vaccines

Even today vaccine(s) remains a mainstay in combating infectious diseases. Many yeast-based vaccines are currently in different phases of clinical trials. Despite the encouraging results of whole recombinant yeast (WRY) and yeast display (YD), the systematic study assessing the long-term stability of protein antigen(s) in yeast cells is still missing. Therefore, in the present study, I investigate the stability of heterologous protein antigen in the cellular environment of S. cerevisiae through E. coli surface protein (major curlin or CsgA). Present biochemical data showed that the stationary phase yeast cells were able to keep the antigen stable for almost one year when stored at 2-8 {degrees}C and 23-25 {degrees}C. Further, iTRAQ based quantitative proteomics of yeast whole cell lysate showed that the level of heterologous fusion protein was low in cells stored at 23-25 {degrees}C compared to those at 2-8 {degrees}C. In the end, I also proposed a workable strategy to test integrity or completeness of heterologous protein in the yeast cell. I believe that the observations made in the present study will be really encouraging for those interested in the development of a whole recombinant yeast-based vaccine(s).

synthetic biology

Modified protocol for quick and large-scale transformation of Pichia pastoris

Over the last couple of decades, methylotrophic yeast, Pichia pastoris emerges as an important yeast species owing to its increasing application in industry and basic biological research. Transformation of Pichia pastoris cells for the introduction of the gene of interest is common practice for expression and purification of a heterologous protein(s). Presently available protocol of Pichia pastoris transformation involves preparation of competent cells and followed by their transformation. Preparation of competent cells requires growth of cells to certain cell density which requires lots of resource, space, time and efforts. This limits the number of transformations that can be performed by an individual at a time. In the present paper, I will describe a modification in the available protocol which makes P. pastoris transformation hassle free. The present procedure does not require growth of pre-culture or growth of cells to certain cell density rather cells are grown in a patch on YPD plate(s) and rest procedure is performed in small eppendrof tubes which allow a large number of transformations in quickest possible time with minimal resource and efforts. In the end, I also compare various protocols in tabular form which allows the user to choose best suitable procedure depending on the available resource, time, number of transformations, requirement, and efforts. The present modified protocol does not require big centrifuge and shaker which further makes this procedure more useful. I believe that present protocol of transformation with its many unique features will be really helpful to those working with P. pastoris.

microbiology

Genome sequence and description of Blautia brookingsii str SG772 nov., a new species of anaerobic bacterium isolated from healthy human gut

Strain SG-772 is a Gram positive, strictly anoxic bacterium isolated from the feces of a healthy human fecal donor. Based on 16S rRNA gene sequence, the strain showed maximum similarity (94.39%) with Blautia stercoris GAM6-1 in EZ-Taxon server and thus assigned the genus Blautia. The scanning electron micrograph of the bacterium revealed the characteristic coccobacillus shape as well as the complete absence of flagellum, suggesting its non-motile phenotype. This strain was found to utilize 27 substrates based on Biolog AN plates assay, with maximum preference for D-mannitol. Additionally, the strain was found to be resistant to tetracycline and streptomycin. Genome sequencing and analysis revealed an overall genome size of 3.49 Mbp and GC content of 43.97%. Based on RAST annotation server, the closest neighbor was Blautia hansenii DSM20583. Average Nucleotide Identity (ANI) of these strains were 81.69%, suggesting a high level of genomic variation. The comparative genome analysis of strain SG772 with B. hansenii DSM20583 revealed a total of 411 orthologous genes coding for basic metabolic functions. Furthermore, the genomes were functionally distinct based on COG categories. Thus, based on all these differences, we propose a novel species of genus Blautia named as Blautia brookingsii SG772.

microbiology

Defective DNA damage repair leads to frequent catastrophic genomic events in murine and human tumors

Chromothripsis and chromoanasynthesis are catastrophic events leading to clustered genomic rearrangements. Whole-genome sequencing revealed frequent chromothripsis or chromoanasynthesis (n= 16/26) in brain tumors developing in mice deficient for factors involved in homologous-recombination-repair or non-homologous-end-joining. Catastrophic events were tightly linked to Myc/Mycn amplification, with increased DNA damage and inefficient apoptotic response already observable at early postnatal stages. Inhibition of repair processes and comparison of the mouse tumors with human medulloblastomas (n=68) and glioblastomas (n=32) identified chromothripsis as associated with MYC/MYCN gains and with DNA repair deficiencies, pointing towards therapeutic opportunities to target DNA repair defects in tumors with complex genomic rearrangements.

cancer biology

Altered Fecal Microbiota and Urine Metabolome as Signatures of Soman Poisoning

The experimental pathophysiology of organophosphorus (OP) chemical exposure has been extensively reported. Here, we describe an altered fecal microbiota and urine metabolome that follows intoxication with soman, a lipophilic G class chemical warfare nerve agent. Non-anaesthetized Sprague-Dawley male rats were subcutaneously administered soman at 0.8 - 1.0 of the median lethal dose (LD50) and evaluated for signs of toxicity. Animals were stratified based on seizing activity to evaluate effects of soman exposure on fecal bacterial biota and urine metabolites. Soman exposure reshaped fecal bacterial biota by preferentially expanding Facklamia, Agrobacterium, Bilophila, Enterobacter, and Morganella genera of the Firmicutes and Proteobacteria phyla, some of which are known to hydrolyze OPs. However, analogous changes were not observed in the bacterial biota of the ileum, which remained the same irrespective of dose or seizing status of animals after exposure. Interestingly, when considering just the seizing status of animals, we found that the urine metabolome was markedly altered. Leukotriene C4, kynurenic acid, 5-hydroxyindoleacetic acid, norepinephrine, and aldosterone were excreted at much higher rates at 72 hrs in seizing animals, consistent with early multi-organ involvement during soman poisoning. However, at 75 days post soman exposure, bacterial biota stabilized and no differences were observed. These findings demonstrate the feasibility of using the dysbiosis of fecal bacterial biota in combination with urine metabolome alterations as forensic evidence for OP exposure temporally.\n\nImportanceThe paucity of assays to determine physiologically relevant OP exposure presents an opportunity to explore the use bacterial sentinels in combination with urine to assess changes in the exposed host. Recent advances in technologies and computational approaches have enabled researches to survey large community level changes of gut bacterial biota and metabolomic changes in various biospecimens. Here, we profile combined changes in bacterial biota and urine metabolome due to chemical warfare OP exposure. The significance of our work is to reveal that monitoring bacterial biota and urine metabolites as surrogates of OP exposure in biospecimens suitable for existing clinical laboratory workflows is plausible without the need for the development of new technology, invasive procedures, or complicated analytical approaches. The larger value of such an approach is that any setting with a moderate clinical chemistry and microbiology capability can determine pre-symptomatic exposure to enhance current triage standards in case of mass exposures, refugee movements, humanitarian missions, and training settings once an algorithm has been validated. In the event of \"potential\" exposures by time or distance, this assay can be further developed to estimate affected radius or time dimension for health monitoring and treatment interventions.

physiology

sFlt-1 commutes unfolded protein response into endoplasmic reticulum stress in trophoblast cells in preeclamptic pregnancies

Preeclampsia (PE) and its subtypes (early and late onset) are serious concerns all across the globe affecting about 8% of total pregnancies and accounts for approximately 60,000 deaths annually with a predominance in developing under-developed and countries. The two-stage model in the progression of this disease, deficient spiral artery remodelling and an imbalance between angiogenic (VEGF) and anti-antigenic factor(s) (sFlt-1) are well established facts pertaining to this disease. The presence of increased sFlt-1, high oxidative stress and Endoplasmic reticulum stress (ER stress) have been proposed in preeclamptic pregnancies. Recently, the role of endoplasmic reticulum stress in the onset of the variant forms of PE highlighted a new window to explore further. In our previous studies, we demonstrated that sFlt-1 can induce apoptosis and oxidative stress in trophoblast cells. However the role of sFlt-1, in inducing ER stress is not known so far. In the present study, we for the first time demonstrated significant ER stress in the placental cells (BeWo Cells) (in vitro) when exposed to sera from preeclamptic pregnancies having increased concentration of sFlt-1. The expression of ER stress markers (GRP78, eIF2, XBP1, ATF6 and CHOP) at both transcript and protein levels were compared (between preeclamptic and normotensive non-proteinuric women) at three different time points (8h, 14h and 24hrs), analyzed and found to be significant (p<0.05).\n\nConclusionOur results suggested that sFlt-1, released from placental cells in preeclampsia may be one of the various factors having potential to induce endoplasmic reticulum stress in BeWo cells.

developmental biology

Targeted Drug Delivery by Radiation-Induced Tumor Vascular Modulation

Effective drug delivery is severely restricted by the presence of complex pathophysiological barriers in solid tumors. In human pancreatic adenocarcinoma, mature and hypopermeable tumor blood vessels limit the permeation and penetration of chemo or nanotherapeutics to cancer cells and substantially reduce the treatment efficacy. New, clinically-viable strategies are therefore sought to breach the neoplastic barriers that prevent optimal tumor-specific drug delivery. Here, we present an original idea to boost targeted drug delivery by selectively knocking down the tumor vascular barrier in a poorly permeable human pancreatic cancer model. For the first time, we demonstrate that clinical irradiation (10 Gy, 6 MV) can induce tumor vascular modulation when combined with tumor endothelial-targeting gold nanoparticles. Active disruption of tumor blood vessels by nanoparticle-combined radiotherapy led to increased vessel permeability and improved tumor uptake of two prototypical model nanodrugs: i) a short-circulating nanocarrier with MR-sensitive gadolinium (Gad-NC; 8 kDa; t1/2=1.5 h) and ii) a long-circulating nanocarrier with fluorescence-sensitive NIR dye (FL-NC; 30 kDa; t1/2=25 h). Functional changes in the altered tumor vessel dynamics, measured by relative changes in permeability (Ktrans), flux rate (Kep) and extracellular interstitial volume (Ve) were consistent with the concomitant increase in nanodrug delivery. This combination of radiation-induced antivascular and nanodrug-mediated anti-tumor treatment offers high therapeutic benefit for tumors with pathophysiology that restricts efficient drug delivery.\n\n\n\nO_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=125 SRC=\"FIGDIR/small/268714_ufig1.gif\" ALT=\"Figure 1\">\nView larger version (84K):\norg.highwire.dtl.DTLVardef@a6df8borg.highwire.dtl.DTLVardef@19e3179org.highwire.dtl.DTLVardef@c223aaorg.highwire.dtl.DTLVardef@1b3a08d_HPS_FORMAT_FIGEXP M_FIG GRAPHICAL ABSTRACT\n\nC_FIG

bioengineering

Effects of different load on physiological, hematological, biochemical, cytokines indices of Zanskar ponies at high altitude

High altitude people required high endurance pack animals for load carrying and riding at prevalent mountainous terrains and rugged region. So far no studies have been taken to evaluate effect of loads on physiology of ponies in high altitude region. So, in this view we evaluated variation in physiological, hematological, biochemical, and cytokines indices of Zanskar ponies during load carrying at high altitude. Total twelve (12) numbers of Zanskar ponies, mare, age 4-6 years, were divided into three groups; group-A (without load), group-B (60 kg), and group-C (80 kg) of back pack loads. Track was very narrow and slippery with gravel, uneven with rocky surface and has a steep gradient of 4 km uphill at altitude 3291 to 3500 m. When we evaluate these parameters, it is understood that the heart rate, pulse rate and respiration rate was significantly (p<0.05) increased in 80 kg group among the three groups. The hematology parameters viz. hemoglobin, PCV, lymphocytes, monocytes%, ESR and eosinophil% significantly (p<0.05) changed in 80 kg group after load carrying among the three groups which was followed by control and 60 kg group. In biochemical parameters viz. LA, LDH, TP, HK, CORT, T3, CRT, AST, CK-MB, GPx, FRAP and IL-6 significantly (p<0.05) changed in 80 kg group after load carrying among the three groups which was followed by control and 60 kg group. The ALT, ALB, GLB, UR and UA significantly (p<0.05) changed in 80 kg group before and after load carrying among the three groups which was followed by control and 60 kg group. It has been concluded that, this result has revealed strong correlation of change in biomarkers level with performance in ponies during load carry. Hence, these parameters might be use for performance of endurance of Zanskar ponies in high mountain region.

physiology

sFlt-1 (sVEGFR1) induces placental endoplasmic reticulum stress in trophoblast cell: implications for the complications in preeclampsia - an in vitro study

BackgroundThe concentration of sFlt-1, a major anti-angiogenic protein in maternal circulation has been seen to be raised in preeclamptic pregnancies. Endoplasmic reticulum (ER) stress represents one of the three (immunological, oxidative and ER stress) major stresses which placenta undergoes during pregnancies. The present study is designed to investigate the role of sFlt-1 in induction of ER stress in trophoblast cells.\n\nMaterials and MethodsMaternal serum levels of anti-angiogenic protein sFlt-1 and central regulator of unfolded protein response GRP78 was measured using sandwich ELISA. The expression of various ER stress markers (GRP78, eIF2, XBP1, ATF6 and apoptotic protein CHOP) were analyzed depending on various treatments given to the trophoblast cells using Immunofluorescence, western blot and q-RT PCR.\n\nResultsIncreased expression of ER stress markers (GRP78, eIF2, XBP1 ATF6 and apoptotic protein CHOP) was detected in the placental trophoblast cells treated with raised concentration of sFlt-1.\n\nConclusionSignificant upregulated expression of ER stress markers in trophoblast cells exposed with increased concentration of sFlt-1 suggested that it may be one of the anti-angiogenic factors present in maternal sera which not only contributes to oxidative stress but also may cause endoplasmic reticulum stress.

developmental biology

The prognostic effects of somatic mutations in ER-positive breast cancer

More than 50 genes are recurrently affected by somatic mutation in estrogen receptor positive (ER+) breast cancer but prognostic effects have not been definitively established. Primary tumor DNA was therefore subjected to targeted sequencing from 625 postmenopausal (UBC-TAM series) and 328 premenopausal (MA12 trial) hormone receptor-positive (HR+) patients. Independent validation of prognostic interactions was achieved using independent data from the METABRIC study. Associations between MAP3K1 and PIK3CA with luminal A status and TP53 mutations with Luminal B/non-luminal tumors were observed, validating the methodological approach. In UBC-TAM, NF1 frame-shift nonsense (FS/NS) mutation was validated as a poor outcome driver. For MA12, poor outcome associated with PIK3R1 mutation was similarly validated. DDR1 mutations were strongly associated with poor prognosis in UBC-TAM despite stringent false-discovery correction (q=0.0003). In conclusion, uncommon recurrent somatic mutations should be further explored to create a more complete explanation of the highly variable outcomes that typify ER+ breast cancer.

genomics

HumCFS: A database of fragile sites in human chromosomes

Genomic instability is the hallmark of cancer and several other pathologies, such as mental retardation; preferentially occur at specific loci in genome known as chromosomal fragile sites. HumCFS (http://webs.iiitd.edu.in/raghava/humcfs/) is a manually curated database provides comprehensive information on 118 experimentally characterized fragile sites present in human chromosomes. HumCFS comprises of 19068 entries with wide range of information such as nucleotide sequence of fragile sites, their length, coordinates on the chromosome, cytoband, their inducers and possibility of fragile site occurrence i.e. either rare or common etc. Each fragile region gene is further annotated to disease database DisGenNET, to understand its disease association. Protein coding genes are identified by annotating each fragile site to UCSC genome browser (GRCh38/hg38). To know the extent of miRNA lying in fragile site region, miRNA from miRBase has been mapped. Comprehensively, HumCFS encompasses mapping of 5010 genes with 19068 transcripts, 1104 miRNA and 3737 disease-associated genes on fragile sites. In order to facilitate users, we integrate standard web-based tools for easy data retrieval and analysis.

bioinformatics

Regulation of thickness of actomyosin cortex in well-spread cells by contractility and spread area

The contractile cortical actomyosin cytoskeleton (or cortex) in interphase cells confers rigidity to cells, but also lead to shape dynamics. Regulation of its thickness, although well studied in rounded cells, is less explored in well-spread cells. In this paper, we quantify the variations in thickness and study the contribution of actin polymerization, myosin II activity and spread area of cells. We report an increase in cortex thickness and its variations on disrupting actin network by actin depolymerizing agents or reducing contractility by inhibiting motor activity of myosin II. On spread area reduction by substrate micropatterning, we find reduced cell volume and increased mean & variability of thickness. To validate, we follow cells through de-adhesion with EDTA. The thickness of cortex increases (and oscillates) while the volume of cells reduces with 5-15 mins timescales. Moreover, total internal reflection fluorescence (TIRF) imaging reveals stress fibre dissolution and events of their buckling along with a growing population of micron-sized mobile filaments. We believe that the cytoskeleton responds to the loss of adhesion by contracting and fragmenting, hence leading to cortex thickening. Limiting volume reduction does not suppress cortex thickening on de-adhesion, suggesting that decreased traction stress may be primarily responsible for the cortex thickening.

biophysics

NAC-NOR mutations in tomato Penjar accessions attenuate multiple metabolic processes and prolong the fruit shelf life

Several Penjar accessions of tomato (Solanum lycopersicum), widely grown in the Mediterranean region, exhibit prolonged shelf life, and harbor alcobaca mutation with valine-106-aspartic acid substitution in the NAC-NOR protein. To uncover the metabolic basis underlying the prolonged shelf life, we compared four Penjar accessions to Ailsa Craig (AC). Three accessions bore alcobaca mutation, whereas fourth was a novel NAC-NOR allele with only six amino acids in the encoded protein. The cuticle composition among Penjars varied widely during the progression of fruit ripening. All Penjars exhibited delayed ripening, prolonged on-vine and off-vine shelf life, low ethylene emission and carotenoid levels albeit with accession-specific differences. Metabolic profiling revealed shifts in Krebs cycle intermediates, amino acids, and {beta}-aminobutyric acid levels indicating the attenuation of respiration in Penjars during post-harvest storage. The prolonged shelf life of Penjar fruits was associated with a concerted downregulation of a number of cell-wall modifying genes and cell-wall-related metabolites. The accumulation of higher ABA and sucrose levels at the onset of senescence in Penjar fruits likely contribute to reduced water loss. Our analyses reveal that in addition to specialized cuticle composition, the attenuation of various metabolic processes by NAC-NOR mutation likely prolongs the shelf life of Penjar fruits.\n\nHighlightThe prolonged shelf life of tomato Penjar accessions bearing mutations in NAC-NOR transcription factor appears to be regulated by a combined effect of attenuation of respiration, altered cuticle composition, enhanced ABA and sucrose levels in fruits and downregulation of cell wall modification

plant biology

Neotrygon indica sp. nov., the Indian-Ocean blue-spotted maskray (Myliobatoidei, Dasyatidae)

The blue-spotted maskray, previously N kuhlii, consists of up to eleven lineages representing separate species. Nine of these species (N australiae, N. bobwardi, N. caeruleopunctata, N. malaccensis, N moluccensis, N orientale, N. vali, N varidens, N westpapuensis) have already been formally described and two (Indian-Ocean maskray and Ryukyu maskray) remain undescribed. Here the Indian-Ocean maskray is described as a new species, Neotrygon indica sp. nov.

zoology

FIGL1 and its novel partner FLIP form a conserved complex that regulates homologous recombination.

Homologous recombination is central to repair DNA double-strand breaks (DSB), either accidently arising in mitotic cells or in a programed manner at meiosis. Crossovers resulting from the repair of meiotic breaks are essential for proper chromosome segregation and increase genetic diversity of the progeny. However, mechanisms regulating CO formation remain elusive. Here, we identified through protein-protein interaction and genetic screens FIDGETIN-LIKE-1 INTERACTING PROTEIN (FLIP) as a new partner of the previously characterized anti-crossover factor FIDGETIN-LIKE-1 (FIGL1) in Arabidopsis thaliana. We showed that FLIP limits meiotic crossover together with FIGL1. Further, FLIP and FIGL1 form a protein complex conserved from Arabidopsis to Human. FIGL1 interacts with the recombinases RAD51 and DMC1, the enzymes that catalyze the DNA stand exchange step of homologous recombination. Arabidopsis flip mutants recapitulates the figl1 phenotype, with enhanced meiotic recombination associated with change in DMC1 dynamics. Our data thus suggest that FLIP and FIGL1 form a conserved complex that regulates the crucial step of strand invasion in homologous recombination.

genetics

A Genome-wide Association and Admixture Mapping Study of Bronchodilator Drug Response in African Americans with Asthma

BackgroundShort-acting B2-adrenergic receptor agonists (SABAs) are the most commonly prescribed asthma medications worldwide. Response to SABAs is measured as bronchodilator drug response (BDR), which varies among racial/ethnic groups in the U.S 1, 2. However, the genetic variation that contributes to BDR is largely undefined in African Americans with asthma3\n\nObjectiveTo identify genetic variants that may contribute to differences in BDR in African Americans with asthma.\n\nMethodsWe performed a genome-wide association study of BDR in 949 African American children with asthma, genotyped with the Axiom World Array 4 (Affymetrix, Santa Clara, CA) followed by imputation using 1000 Genomes phase 3 genotypes. We used linear regression models adjusting for age, sex, body mass index and genetic ancestry to test for an association between BDR and genotype at single nucleotide polymorphisms (SNPs). To increase power and distinguish between shared vs. population-specific associations with BDR in children with asthma, we performed a meta-analysis across 949 African Americans and 1,830 Latinos (Total=2,779). Lastly, we performed genome-wide admixture mapping to identify regions whereby local African or European ancestry is associated with BDR in African Americans. Two additional populations of 416 Latinos and 1,325 African Americans were used to replicate significant associations.\n\nResultsWe identified a population-specific association with an intergenic SNP on chromosome 9q21 that was significantly associated with BDR (rs73650726, p=7.69 x 10-9). A trans-ethnic meta-analysis across African Americans and Latinos identified three additional SNPs within the intron of PRKG1 that were significantly associated with BDR (rs7903366, rs7070958, and rs7081864, p[&le;]5 x 10-8).\n\nConclusionsOur findings indicate that both population specific and shared genetic variation contributes to differences in BDR in minority children with asthma, and that the genetic underpinnings of BDR may differ between racial/ethnic groups.\n\nKey messagesO_LIA GWAS for BDR in African American children with asthma identified an intergenic population specific variant at 9q21 to be associated with increased bronchodilator drug response (BDR).\nC_LIO_LIA meta-analysis of GWAS across African Americans and Latinos identified shared genetic variants at 10q21 in the intron of PRKG1 to be associated with differences in BDR.\nC_LIO_LIFurther genetic studies need to be performed in diverse populations to identify the full set of genetic variants that contribute to BDR.\nC_LI

genomics