RESUMO
Nitrogen (N(2))-fixing marine cyanobacteria are an important source of fixed inorganic nitrogen that supports oceanic primary productivity and carbon dioxide removal from the atmosphere. A globally distributed, periodically abundant N(2)-fixing marine cyanobacterium, UCYN-A, was recently found to lack the oxygen-producing photosystem II complex of the photosynthetic apparatus, indicating a novel metabolism, but remains uncultivated. Here we show, from metabolic reconstructions inferred from the assembly of the complete UCYN-A genome using massively parallel pyrosequencing of paired-end reads, that UCYN-A has a photofermentative metabolism and is dependent on other organisms for essential compounds. We found that UCYN-A lacks a number of major metabolic pathways including the tricarboxylic acid cycle, but retains sufficient electron transport capacity to generate energy and reducing power from light. Unexpectedly, UCYN-A has a reduced genome (1.44 megabases) that is structurally similar to many chloroplasts and some bacteria, in that it contains inverted repeats of ribosomal RNA operons. The lack of biosynthetic pathways for several amino acids and purines suggests that this organism depends on other organisms, either in close association or in symbiosis, for critical nutrients. However, size fractionation experiments using natural populations have so far not provided evidence of a symbiotic association with another microorganism. The UCYN-A cyanobacterium is a paradox in evolution and adaptation to the marine environment, and is an example of the tight metabolic coupling between microorganisms in oligotrophic oceanic microbial communities.
Assuntos
Cianobactérias/genética , Cianobactérias/metabolismo , Genoma Bacteriano/genética , Fixação de Nitrogênio/fisiologia , Nitrogênio/metabolismo , Água do Mar/microbiologia , Carbono/metabolismo , Cromossomos Bacterianos/genética , Cianobactérias/classificação , Cianobactérias/citologia , Transporte de Elétrons , Genômica , Biologia Marinha , Dados de Sequência Molecular , Fixação de Nitrogênio/genética , Oceanos e Mares , Oxirredutases/genéticaRESUMO
The human distal gut harbours a vast ensemble of microbes (the microbiota) that provide important metabolic capabilities, including the ability to extract energy from otherwise indigestible dietary polysaccharides. Studies of a few unrelated, healthy adults have revealed substantial diversity in their gut communities, as measured by sequencing 16S rRNA genes, yet how this diversity relates to function and to the rest of the genes in the collective genomes of the microbiota (the gut microbiome) remains obscure. Studies of lean and obese mice suggest that the gut microbiota affects energy balance by influencing the efficiency of calorie harvest from the diet, and how this harvested energy is used and stored. Here we characterize the faecal microbial communities of adult female monozygotic and dizygotic twin pairs concordant for leanness or obesity, and their mothers, to address how host genotype, environmental exposure and host adiposity influence the gut microbiome. Analysis of 154 individuals yielded 9,920 near full-length and 1,937,461 partial bacterial 16S rRNA sequences, plus 2.14 gigabases from their microbiomes. The results reveal that the human gut microbiome is shared among family members, but that each person's gut microbial community varies in the specific bacterial lineages present, with a comparable degree of co-variation between adult monozygotic and dizygotic twin pairs. However, there was a wide array of shared microbial genes among sampled individuals, comprising an extensive, identifiable 'core microbiome' at the gene, rather than at the organismal lineage, level. Obesity is associated with phylum-level changes in the microbiota, reduced bacterial diversity and altered representation of bacterial genes and metabolic pathways. These results demonstrate that a diversity of organismal assemblages can nonetheless yield a core microbiome at a functional level, and that deviations from this core are associated with different physiological states (obese compared with lean).
Assuntos
Trato Gastrointestinal/microbiologia , Metagenoma/fisiologia , Obesidade/microbiologia , Magreza/microbiologia , Adulto , África/etnologia , Biodiversidade , Meio Ambiente , Europa (Continente)/etnologia , Fezes/microbiologia , Feminino , Genótipo , Humanos , Metagenoma/genética , Missouri , Dados de Sequência Molecular , Mães , RNA Ribossômico 16S/análise , RNA Ribossômico 16S/genética , Gêmeos Dizigóticos , Gêmeos MonozigóticosRESUMO
Human intervention has subjected the yeast Saccharomyces cerevisiae to multiple rounds of independent domestication and thousands of generations of artificial selection. As a result, this species comprises a genetically diverse collection of natural isolates as well as domesticated strains that are used in specific industrial applications. However the scope of genetic diversity that was captured during the domesticated evolution of the industrial representatives of this important organism remains to be determined. To begin to address this, we have produced whole-genome assemblies of six commercial strains of S. cerevisiae (four wine and two brewing strains). These represent the first genome assemblies produced from S. cerevisiae strains in their industrially-used forms and the first high-quality assemblies for S. cerevisiae strains used in brewing. By comparing these sequences to six existing high-coverage S. cerevisiae genome assemblies, clear signatures were found that defined each industrial class of yeast. This genetic variation was comprised of both single nucleotide polymorphisms and large-scale insertions and deletions, with the latter often being associated with ORF heterogeneity between strains. This included the discovery of more than twenty probable genes that had not been identified previously in the S. cerevisiae genome. Comparison of this large number of S. cerevisiae strains also enabled the characterization of a cluster of five ORFs that have integrated into the genomes of the wine and bioethanol strains on multiple occasions and at diverse genomic locations via what appears to involve the resolution of a circular DNA intermediate. This work suggests that, despite the scrutiny that has been directed at the yeast genome, there remains a significant reservoir of ORFs and novel modes of genetic transmission that may have significant phenotypic impact in this important model and industrial species.
Assuntos
Cerveja/microbiologia , Genoma Fúngico/genética , Microbiologia Industrial , Saccharomyces cerevisiae/genética , Vinho/microbiologia , Sequência de Bases , Biologia Computacional , Evolução Molecular , Variação Genética , Mutação INDEL/genética , Dados de Sequência Molecular , Fases de Leitura Aberta/genética , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
The Actinomycetales bacteria Rhodococcus opacus PD630 and Rhodococcus jostii RHA1 bioconvert a diverse range of organic substrates through lipid biosynthesis into large quantities of energy-rich triacylglycerols (TAGs). To describe the genetic basis of the Rhodococcus oleaginous metabolism, we sequenced and performed comparative analysis of the 9.27 Mb R. opacus PD630 genome. Metabolic-reconstruction assigned 2017 enzymatic reactions to the 8632 R. opacus PD630 genes we identified. Of these, 261 genes were implicated in the R. opacus PD630 TAGs cycle by metabolic reconstruction and gene family analysis. Rhodococcus synthesizes uncommon straight-chain odd-carbon fatty acids in high abundance and stores them as TAGs. We have identified these to be pentadecanoic, heptadecanoic, and cis-heptadecenoic acids. To identify bioconversion pathways, we screened R. opacus PD630, R. jostii RHA1, Ralstonia eutropha H16, and C. glutamicum 13032 for growth on 190 compounds. The results of the catabolic screen, phylogenetic analysis of the TAGs cycle enzymes, and metabolic product characterizations were integrated into a working model of prokaryotic oleaginy.
Assuntos
Biocombustíveis , Lipídeos/biossíntese , Redes e Vias Metabólicas/genética , Rhodococcus/genética , Triglicerídeos/biossíntese , Ácidos Graxos/genética , Ácidos Graxos/metabolismo , Genoma Bacteriano , Genômica , Filogenia , Rhodococcus/metabolismo , Triglicerídeos/genéticaRESUMO
Hybridization between distantly related organisms can facilitate rapid adaptation to novel environments, but is potentially constrained by epistatic fitness interactions among cell components. The zoonotic pathogens Campylobacter coli and C. jejuni differ from each other by around 15% at the nucleotide level, corresponding to an average of nearly 40 amino acids per protein-coding gene. Using whole genome sequencing, we show that a single C. coli lineage, which has successfully colonized an agricultural niche, has been progressively accumulating C. jejuni DNA. Members of this lineage belong to two groups, the ST-828 and ST-1150 clonal complexes. The ST-1150 complex is less frequently isolated and has undergone a substantially greater amount of introgression leading to replacement of up to 23% of the C. coli core genome as well as import of novel DNA. By contrast, the more commonly isolated ST-828 complex bacteria have 10-11% introgressed DNA, and C. jejuni and nonagricultural C. coli lineages each have <2%. Thus, the C. coli that colonize agriculture, and consequently cause most human disease, have hybrid origin, but this cross-species exchange has so far not had a substantial impact on the gene pools of either C. jejuni or nonagricultural C. coli. These findings also indicate remarkable interchangeability of basic cellular machinery after a prolonged period of independent evolution.
Assuntos
Campylobacter coli/genética , Campylobacter jejuni/genética , Evolução Molecular , Genoma Bacteriano , Hibridização Genética , Campylobacter coli/isolamento & purificação , Campylobacter jejuni/isolamento & purificação , DNA Bacteriano/genética , Funções Verossimilhança , Modelos Genéticos , Análise de Sequência de DNARESUMO
The oomycete vegetable pathogen Phytophthora capsici has shown remarkable adaptation to fungicides and new hosts. Like other members of this destructive genus, P. capsici has an explosive epidemiology, rapidly producing massive numbers of asexual spores on infected hosts. In addition, P. capsici can remain dormant for years as sexually recombined oospores, making it difficult to produce crops at infested sites, and allowing outcrossing populations to maintain significant genetic variation. Genome sequencing, development of a high-density genetic map, and integrative genomic or genetic characterization of P. capsici field isolates and intercross progeny revealed significant mitotic loss of heterozygosity (LOH) in diverse isolates. LOH was detected in clonally propagated field isolates and sexual progeny, cumulatively affecting >30% of the genome. LOH altered genotypes for more than 11,000 single-nucleotide variant sites and showed a strong association with changes in mating type and pathogenicity. Overall, it appears that LOH may provide a rapid mechanism for fixing alleles and may be an important component of adaptability for P. capsici.
Assuntos
Phytophthora/fisiologia , Doenças das Plantas/microbiologia , Adaptação Fisiológica , Capsicum/microbiologia , Mapeamento Cromossômico , Cucurbita/microbiologia , Regulação da Expressão Gênica , Ligação Genética , Genoma , Genótipo , Polimorfismo de Nucleotídeo ÚnicoRESUMO
The vast majority of wine fermentations are performed principally by Saccharomyces cerevisiae. However, there are a growing number of instances in which other species of Saccharomyces play a predominant role. Interestingly, the presence of these other yeast species generally occurs via the formation of interspecific hybrids that contain genomic contributions from both S. cerevisiae and non-S. cerevisiae species. However, despite the large number of wine strains that are characterized at the genomic level, there remains limited information regarding the detailed genomic structure of hybrids used in winemaking. To address this, we describe the genome sequence of the thiol-releasing commercial wine yeast hybrid VIN7. VIN7 is shown to be an almost complete allotriploid interspecific hybrid that is comprised of a heterozygous diploid complement of S. cerevisiae chromosomes and a haploid Saccharomyces kudriavzevii genomic contribution. Both parental strains appear to be of European origin, with the S. cerevisiae parent being closely related to, but distinct from, the commercial wine yeasts QA23 and EC1118. In addition, several instances of chromosomal rearrangement between S. cerevisiae and S. kudriavzevii sequences were observed that may mark the early stages of hybrid genome consolidation.
Assuntos
Quimera/genética , Genoma Fúngico , Saccharomyces/genética , Triploidia , Vinho/microbiologia , DNA Fúngico/química , DNA Fúngico/genética , Evolução Molecular , Rearranjo Gênico , Dados de Sequência Molecular , Recombinação Genética , Saccharomyces/isolamento & purificação , Análise de Sequência de DNARESUMO
Previous quantitative trait locus (QTL) analysis of an intercross involving the inbred mouse strains NZB/BlNJ and SM/J revealed QTL for a variety of complex traits. Many QTL have large intervals containing hundreds of genes, and methods are needed to rapidly sort through these genes for probable candidates. We chose nine QTL: the three most significant for high-density lipoprotein (HDL) cholesterol, gallstone formation, and obesity. We searched for candidate genes using three different approaches: mRNA microarray gene expression technology to assess >45,000 transcripts, publicly available SNPs to locate genes that are not identical by descent and that contain nonsynonymous coding differences, and a mass-spectrometry-based proteomics technology to interrogate nearly 1000 proteins for differential expression in the liver of the two parental inbred strains. This systematic approach reduced the number of candidate genes within each QTL from hundreds to a manageable list. Each of the three approaches selected candidates that the other two approaches missed. For example, candidate genes such as Apoa2 and Acads had differential protein levels although the mRNA levels were similar. We conclude that all three approaches are important and that focusing on a single approach such as mRNA expression may fail to identify a QTL gene.
Assuntos
Regulação da Expressão Gênica , Polimorfismo de Nucleotídeo Único/genética , Proteômica/métodos , Característica Quantitativa Herdável , Animais , Western Blotting , Códon/genética , Cruzamentos Genéticos , Feminino , Perfilação da Expressão Gênica , Masculino , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos , Fases de Leitura Aberta/genética , Proteínas/química , Proteínas/genética , Locos de Características Quantitativas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
Gonadal sex determining (GSD) genes that initiate fetal ovarian and testicular development and differentiation are expressed in the cells of the urogenital ridge that differentiate as somatic support cells (SSCs), i.e., granulosa cells of the ovary and Sertoli cells of the testis. To identify potential new mammalian GSD genes, we used the Mouse Genome 430v2.0 GeneChip to analyze gene expression differences between XX and XY SSCs cells isolated from the gonads of embryonic day (E) 13 C57BL/6J fetuses carrying an EGFP reporter transgene expressed specifically in SSCs. In addition, genome wide expression differences between XX and XY E13 whole gonads were examined. Analysis revealed that XX and XY E13 SSCs differentially express 647 transcripts (False Discovery Rate cutoff 1%), including transcripts not previously reported to exhibit a sexually dimorphic expression pattern in this unique cell population. Enrichment for genes controlling cell proliferation was noted in XY SSCs, whereas enrichment for genes controlling cell morphology and metabolic status was identified in XX SSCs. Among the newly identified differentially expressed transcripts are potential GSD genes involved in unexplained human sex reversal cases.
Assuntos
Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Células da Granulosa/citologia , Células da Granulosa/metabolismo , Células de Sertoli/citologia , Células de Sertoli/metabolismo , Animais , Diferenciação Celular , Transtornos do Desenvolvimento Sexual , Feminino , Perfilação da Expressão Gênica , Disgenesia Gonadal/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Análise de Sequência com Séries de Oligonucleotídeos , Ovário/citologia , Ovário/embriologia , Ovário/metabolismo , Gravidez , Caracteres Sexuais , Processos de Determinação Sexual , Testículo/citologia , Testículo/embriologia , Testículo/metabolismoRESUMO
We describe a transcriptional analysis platform consisting of a universal micro-array system (UMAS) combined with an enzymatic manipulation step that is capable of generating expression profiles from any organism without requiring a priori species-specific knowledge of transcript sequences. The transcriptome is converted to cDNA and processed with restriction endonucleases to generate low-complexity pools (approximately 80-120) of equal length DNA fragments. The resulting material is amplified and detected with the UMAS system, comprising all possible 4,096 (4(6)) DNA hexamers. Ligation to the arrays yields thousands of 14-mer sequence tags. The compendium of signals from all pools in the array-of-universal arrays comprises a full-transcriptome expression profile. The technology was validated by analysis of the galactose response of Saccharomyces cerevisiae, and the resulting profiles showed excellent agreement with the literature and real-time PCR assays. The technology was also used to demonstrate expression profiling from a hybrid organism in a proof-of-concept experiment where a T-cell receptor gene was expressed in yeast.
Assuntos
Perfilação da Expressão Gênica/métodos , Análise de Sequência com Séries de Oligonucleotídeos , Regiões 3' não Traduzidas , Algoritmos , Animais , Fragmentação do DNA , Enzimas de Restrição do DNA/metabolismo , DNA Complementar/metabolismo , Galactose/metabolismo , Humanos , Processamento de Imagem Assistida por Computador , Camundongos , Modelos Genéticos , Músculo Esquelético/metabolismo , Músculos/metabolismo , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Saccharomyces cerevisiae/metabolismo , Análise de Sequência de DNA , Linfócitos T/metabolismo , TransgenesRESUMO
BACKGROUND: The cytokine-deficiency-induced colitis susceptibility (Cdcs)1 locus is a major modifier of murine inflammatory bowel disease (IBD) and was originally identified in experimental crosses of interleukin-10-deficient (Il10(-/-)) mice. Congenic mice, in which this locus was reciprocally transferred between IBD-susceptible C3H/HeJBir-Il10(-/-) and resistant C57BL/6J-Il10(-/-) mice, revealed that this locus likely acts by inducing innate hypo- and adaptive hyperresponsiveness, associated with impaired NF-kappaB responses of macrophages. The aim of the present study was to dissect the complexity of Cdcs1 by further development and characterization of reciprocal Cdcs1 congenic strains and to identify potential candidate genes in the congenic interval. METHODS: In total, 15 reciprocal congenic strains were generated from Il10(-/-) mice of either C3H/HeJBir or C57BL/6J genetic backgrounds by 10 cycles of backcrossing. Colitis activity was monitored by histological grading. Candidate genes were identified by fine mapping of congenic intervals, sequencing, microarray analysis, and a high-throughput real-time reverse-transcription polymerase chain reaction (RT-PCR) approach using bone marrow-derived macrophages. RESULTS: Within the originally identified Cdcs1-interval, 3 independent regions were detected that likely contain susceptibility-determining genetic factors (Cdcs1.1, Cdcs1.2, and Cdcs1.3). Combining results of candidate gene approaches revealed Fcgr1, Cnn3, Larp7, and Alpk1 as highly attractive candidate genes with polymorphisms in coding or regulatory regions and expression differences between susceptible and resistant mouse strains. CONCLUSIONS: Subcongenic analysis of the major susceptibility locus Cdcs1 on mouse chromosome 3 revealed a complex genetic structure. Candidate gene approaches revealed attractive genes within the identified regions.
Assuntos
Biomarcadores Tumorais/genética , Colite/genética , Predisposição Genética para Doença , Interleucina-10/fisiologia , Animais , Biomarcadores Tumorais/metabolismo , Western Blotting , Colite/patologia , Feminino , Perfilação da Expressão Gênica , Masculino , Camundongos , Camundongos Congênicos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Oocyte-derived bone morphogenetic protein 15 (BMP15) and growth differentiation factor 9 (GDF9) are key regulators of follicular development. Here we show that these factors control cumulus cell metabolism, particularly glycolysis and cholesterol biosynthesis before the preovulatory surge of luteinizing hormone. Transcripts encoding enzymes for cholesterol biosynthesis were downregulated in both Bmp15(-/-) and Bmp15(-/-) Gdf9(+/-) double mutant cumulus cells, and in wild-type cumulus cells after removal of oocytes from cumulus-cell-oocyte complexes. Similarly, cholesterol synthesized de novo was reduced in these cumulus cells. This indicates that oocytes regulate cumulus cell cholesterol biosynthesis by promoting the expression of relevant transcripts. Furthermore, in wild-type mice, Mvk, Pmvk, Fdps, Sqle, Cyp51, Sc4mol and Ebp, which encode enzymes required for cholesterol synthesis, were highly expressed in cumulus cells compared with oocytes; and oocytes, in the absence of the surrounding cumulus cells, synthesized barely detectable levels of cholesterol. Furthermore, coincident with reduced cholesterol synthesis in double mutant cumulus cells, lower levels were also detected in cumulus-cell-enclosed double mutant oocytes compared with wild-type oocytes. Levels of cholesterol synthesis in double mutant cumulus cells and oocytes were partially restored by co-culturing with wild-type oocytes. Together, these results indicate that mouse oocytes are deficient in synthesizing cholesterol and require cumulus cells to provide products of the cholesterol biosynthetic pathway. Therefore, oocyte-derived paracrine factors, particularly, BMP15 and GDF9, promote cholesterol biosynthesis in cumulus cells, probably as compensation for oocyte deficiencies in cholesterol production.
Assuntos
Colesterol/biossíntese , Células do Cúmulo/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Oócitos/metabolismo , Animais , Proteína Morfogenética Óssea 15 , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Fator 9 de Diferenciação de Crescimento , Peptídeos e Proteínas de Sinalização Intercelular/deficiência , Peptídeos e Proteínas de Sinalização Intercelular/genética , Camundongos , Camundongos Knockout , Mutação/genética , RNA Mensageiro/genética , Transcrição Gênica/genéticaRESUMO
Biological nitrogen (N2) fixation is important in controlling biological productivity and carbon flux in the oceans. Unicellular N2-fixing cyanobacteria have only recently been discovered and are widely distributed in tropical and subtropical seas. Metagenomic analysis of flow cytometry-sorted cells shows that unicellular N2-fixing cyanobacteria in "group A" (UCYN-A) lack genes for the oxygen-evolving photosystem II and for carbon fixation, which has implications for oceanic carbon and nitrogen cycling and raises questions regarding the evolution of photosynthesis and N2 fixation on Earth.
Assuntos
Cianobactérias/genética , Cianobactérias/metabolismo , Fixação de Nitrogênio/genética , Complexo de Proteína do Fotossistema II/genética , Água do Mar/microbiologia , Cianobactérias/citologia , Cianobactérias/isolamento & purificação , Evolução Molecular , Citometria de Fluxo , Genes Bacterianos , Genes de RNAr , Genoma Bacteriano , Genômica/métodos , Dados de Sequência Molecular , Oxirredutases/genética , Oceano Pacífico , Fotossíntese , Complexo de Proteína do Fotossistema II/metabolismo , FilogeniaRESUMO
Lipodystrophies are syndromes of adipose tissue degeneration associated with severe defects in lipid and glucose homeostasis. We report here the generation and analysis of Pparg(ldi), a targeted allele that confers conditional dominant lipodystrophy in mice. The Pparg(ldi) allele was generated by insertion of the Tet activator (tTA) and a tTA-regulated Flag-Pparg1 transgene into the Pparg gene. Unexpectedly, tTA elicits mild lipodystrophy, insulin resistance, and dyslipidemia, and the Flag-PPARgamma1 transgene surprisingly exacerbates these traits. Doxycycline can both completely prevent and reverse these phenotypes, providing a mouse model of inducible lipodystrophy. Embryonic fibroblasts from either Pparg(ldi/+) or the phenotypically similar aP2-nSrebp1c (Sr) transgenic mice undergo robust adipogenesis, suggesting that neither strain develops lipodystrophy because of defective adipocyte differentiation. In addition, Pparg(ldi/+) adipose tissue shares extensive gene expression aberrations with that of Sr mice, authenticating the phenotype at the molecular level and revealing a common expression signature of lipodystrophic fat. Thus, the Pparg(ldi/+) mouse provides a conditional animal model for studying lipodystrophy and its associated physiology and gene expression.
Assuntos
Modelos Animais de Doenças , Lipodistrofia/genética , Camundongos Transgênicos , PPAR gama/genética , Adipogenia/genética , Alelos , Animais , Doxiciclina/farmacologia , Fibroblastos/metabolismo , Expressão Gênica , Resistência à Insulina/genética , Lipodistrofia/patologia , Camundongos , Regiões Promotoras Genéticas/efeitos dos fármacos , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Tetraciclina/farmacologia , Transativadores/genéticaRESUMO
Structural variation of the genome involves kilobase- to megabase-sized deletions, duplications, insertions, inversions, and complex combinations of rearrangements. We introduce high-throughput and massive paired-end mapping (PEM), a large-scale genome-sequencing method to identify structural variants (SVs) approximately 3 kilobases (kb) or larger that combines the rescue and capture of paired ends of 3-kb fragments, massive 454 sequencing, and a computational approach to map DNA reads onto a reference genome. PEM was used to map SVs in an African and in a putatively European individual and identified shared and divergent SVs relative to the reference genome. Overall, we fine-mapped more than 1000 SVs and documented that the number of SVs among humans is much larger than initially hypothesized; many of the SVs potentially affect gene function. The breakpoint junction sequences of more than 200 SVs were determined with a novel pooling strategy and computational analysis. Our analysis provided insights into the mechanisms of SV formation in humans.