Whole-genome analysis reveals distinct adaptation signatures to diverse environments in Chinese domestic pigs

Background Long-term natural and artificial selection has resulted in many genetic footprints within the genomes of pig breeds across distinct agroecological zones.Nevertheless,the mechanisms by which these signatures contribute to phenotypic diversity and facilitate environmental adaptation remain unclear.Results Here,we leveraged whole-genome sequencing data from 82 individuals from 6 domestic pig breeds originating in tropical,high-altitude,and frigid regions.Population genetic analysis suggested that habitat isolation significantly shaped the genetic diversity and contributed to population stratification in local Chinese pig breeds.Analysis of selection signals revealed regions under selection for adaptation in tropical(55.5 Mb),high-altitude(43.6 Mb),and frigid(17.72 Mb)regions.The potential functions of the selective sweep regions were linked to certain complex traits that might play critical roles in different geographic environments,including fat coverage in frigid environments and blood indicators in tropical and high-altitude environments.Candidate genes under selection were significantly enriched in biological pathways involved in environmental adaptation.These pathways included blood circulation,protein degradation,and inflammation for adaptation to tropical environments;heart and lung development,hypoxia response,and DNA damage repair for high-altitude adaptation;and thermogenesis,cold-induced vasodilation(CIVD),and the cell cycle for adaptation to frigid environments.By examining the chromatin state of the selection signatures,we identified the lung and ileum as two candidate functional tissues for environmental adaptation.Finally,we identified a mutation(chr1:G246,175,129A)in the cis-regulatory region of ABCA1 as a plausible promising variant for adaptation to tropical environments.Conclusions In this study,we conducted a genome-wide exploration of the genetic mechanisms underlying the adaptability of local Chinese pig breeds to tropical,high-altitude,and frigid environments.Our findings shed light on the prominent role of cis-regulatory elements in environmental adaptation in pigs and may serve as a valuable biological model of human plateau-related disorders and cardiovascular diseases.

Inferring Mycobacterium Tuberculosis Drug Resistance and Transmission using Whole-genome Sequencing in a High TB-burden Setting in China

Objective China is among the 30 countries with a high burden of tuberculosis(TB)worldwide,and TB remains a public health concern.Kashgar Prefecture in the southern Xinjiang Autonomous Region is considered as one of the highest TB burden regions in China.However,molecular epidemiological studies of Kashgar are lacking.Methods A population-based retrospective study was conducted using whole-genome sequencing(WGS)to determine the characteristics of drug resistance and the transmission patterns.Results A total of 1,668 isolates collected in 2020 were classified into lineages 2(46.0%),3(27.5%),and 4(26.5%).The drug resistance rates revealed by WGS showed that the top three drugs in terms of the resistance rate were isoniazid(7.4%,124/1,668),streptomycin(6.0%,100/1,668),and rifampicin(3.3%,55/1,668).The rate of rifampicin resistance was 1.8%(23/1,290)in the new cases and 9.4%(32/340)in the previously treated cases.Known resistance mutations were detected more frequently in lineage 2 strains than in lineage 3 or 4 strains,respectively:18.6%vs.8.7 or 9%,P<0.001.The estimated proportion of recent transmissions was 25.9%(432/1,668).Multivariate logistic analyses indicated that sex,age,occupation,lineage,and drug resistance were the risk factors for recent transmission.Despite the low rate of drug resistance,drug-resistant strains had a higher risk of recent transmission than the susceptible strains(adjusted odds ratio,1.414;95%CI,1.023–1.954;P=0.036).Among all patients with drug-resistant tuberculosis(DR-TB),78.4%(171/218)were attributed to the transmission of DR-TB strains.Conclusion Our results suggest that drug-resistant strains are more transmissible than susceptible strains and that transmission is the major driving force of the current DR-TB epidemic in Kashgar.

Deciphering the population structure and genetic basis of growth traits from whole-genome resequencing of the leopard coral grouper(Plectropomus leopardus)

The leopard coral grouper(Plectropomus leopardus)is a species of significant economic importance.Although artificial cultivation of P.leopardus has thrived in recent decades,the advancement of selective breeding has been hindered by the lack of comprehensive population genomic data.In this study,we identified over 8.73 million single nucleotide polymorphisms(SNPs)through whole-genome resequencing of 326 individuals spanning six distinct groups.Furthermore,we categorized 226 individuals with high-coverage sequencing depth(≥14×)into eight clusters based on their genetic profiles and phylogenetic relationships.Notably,four of these clusters exhibited pronounced genetic differentiation compared with the other populations.To identify potentially advantageous loci for P.leopardus,we examined genomic regions exhibiting selective sweeps by analyzing the nucleotide diversity(θπ)and fixation index(FST)in these four clusters.Using these high-coverage resequencing data,we successfully constructed the first haplotype reference panel specific to P.leopardus.This achievement holds promise for enabling high-quality,cost-effectiveimputationmethods.Additionally,we combined low-coverage sequencing data with imputation techniques for a genome-wide association study,aiming to identify candidate SNP loci and genes associated with growth traits.A significant concentration of these genes was observed on chromosome 17,which is primarily involved in skeletal muscle and embryonic development and cell proliferation.Notably,our detailed investigation of growth-related SNPs across the eight clusters revealed that cluster 5 harbored the most promising candidate SNPs,showing potential for genetic selective breeding efforts.These findings provide a robust toolkit and valuable insights into the management of germplasm resources and genome-driven breeding initiatives targeting P.leopardus.

QTL mapping of quality traits in peanut using whole-genome resequencing

Oil and protein content and fatty acid composition are quality traits in peanut.Elucidating the genetic mechanisms underlying these traits may help researchers to obtain improved cultivars by molecular breeding.Whole-genome resequencing of a recombinant inbred population of 318 lines was performed to construct a high-density linkage map and identify QTL for peanut quality.The map,containing 4561 bin markers,covered 2032 c M with a mean marker density of 0.45 c M.A total of 110 QTL for oil and protein content,and fatty acid composition were mapped on the 18 peanut chromosomes.The QTL q A05.1 was detected in four environments and showed a major phenotypic effect on the contents of oil,protein,and six fatty acids.The genomic region spanned by q A05.1,corresponding to a physical interval of approximately 1.5 Mb,contains two SNPs polymorphic between the parents that could cause missense mutations.The two SNP sites were employed as KASP markers and validated using lines with extremely high and low oil contents.These sites may be useful in the marker-assisted breeding of peanut cultivars with high oil contents.

Whole-genome resequencing reveals recent signatures of selection in five populations of largemouth bass(Micropterus salmoides)

Largemouth bass(Micropterus salmoides) is an economically important fish species in North America, Europe, and China. Various genetic improvement programs and domestication processes have modified its genome sequence through selective pressure, leaving nucleotide signals that can be detected at the genomic level. In this study,we sequenced 149 largemouth bass fish, including protospecies(imported from the US) and improved breeds(four domestic breeding populations from China). We detected genomic regions harboring certain genes associated with improved traits, which may be useful molecular markers for practical domestication, breeding, and selection. Subsequent analyses of genetic diversity and population structure revealed that the improved breeds have undergone more rigorous genetic changes. Through selective signal analysis, we identified hundreds of putative selective sweep regions in each largemouth bass line. Interestingly, we predicted 103 putative candidate genes potentially subjected to selection,including several associated with growth(psst1 and grb10), early development(klf9, sp4, and sp8), and immune traits(pkn2, sept2, bcl6, and ripk2). These candidate genes represent potential genomic landmarks that could be used to improve important traits of biological and commercial interest. In summary, this study provides a genome-wide map of genetic variations and selection footprints in largemouth bass, which may benefit genetic studies and accelerate genetic improvement of this economically important fish.

Genome-wide scan for selection signatures based on whole-genome re-sequencing in Landrace and Yorkshire pigs

We performed a genome-wide scan to detect selection signatures that showed evidence of positive selection in the domestication process by re-sequencing the whole genomes of Landrace and Yorkshire pigs.Fifteen annotated elements with 13 associated genes were identified using the Z-transformed FST(Z(FST))method,and 208 annotated elements with 140 associated genes were identified using the Z-transformed heterozygosity(ZHp)method.The functional analysis and the results of previous studies showed that most of the candidate genes were associated with basic metabolism,disease resistance,cellular processes,and biochemical signals,and several were related to body morphology and organs.They included PPP3CA,which plays an essential role in the transduction of intracellular Ca2+-mediated signals,and WWTR1,which plays a pivotal role in organ size control and tumor suppression.These results suggest that genes associated with body morphology were subject to selection pressure during domestication,whereas genes involved in basic metabolism and disease resistance were subject to selection during artificial breeding.Our findings provide new insights into the potential genetic variation of phenotypic diversity in different pig breeds and will help to better understand the selection effects of modern breeding in Landrace and Yorkshire pigs.

Whole-genome resequencing reveals molecular imprints of anthropogenic and natural selection in wild and domesticated sheep

The abundance of domesticated sheep varieties and phenotypes is largely the result of long-term natural and artificial selection. However, there is limited information regarding the genetic mechanisms underlying phenotypic variation induced by the domestication and improvement of sheep. In this study, to explore genomic diversity and selective regions at the genome level, we sequenced the genomes of 100 sheep across 10 breeds and combined these results with publicly available genomic data from 225 individuals, including improved breeds, Chinese indigenous breeds,African indigenous breeds, and their Asian mouflon ancestor. Based on population structure, the domesticated sheep formed a monophyletic group,while the Chinese indigenous sheep showed a clear geographical distribution trend. Comparative genomic analysis of domestication identified several selective signatures, including IFI44 and IFI44L genes and PANK2 and RNF24 genes, associated with immune response and visual function.Population genomic analysis of improvement demonstrated that candidate genes of selected regions were mainly associated with pigmentation,energy metabolism, and growth development.Furthermore, the IFI44 and IFI44L genes showed a common selection signature in the genomes of 30domesticated sheep breeds. The IFI44 c. 54413058C>G mutation was selected for genotyping and population genetic validation. Results showed that the IFI44 polymorphism was significantly associated with partial immune traits. Our findings identified the population genetic basis of domesticated sheep at the whole-genome level, providing theoretical insights into the molecular mechanism underlying breed characteristics and phenotypic changes during sheep domestication and improvement.

QTL mapping for berry shape based on a high-density genetic map constructed by whole-genome resequencing in grape

Grape berry shape is an important agricultural trait.Clarifying its genetic basis is significant for cultivating grape varieties that meet market demands.However,the current study by forward genetics has not achieved in-depth results.Here,a high-density map was constructed to identify quantitative trait loci(QTLs)for berry shape.A total of 358709 polymorphic SNPs were obtained using whole-genome resequencing(WGS)based on 208 F2 individuals derived from round grape‘E42-6’and oblong grape‘Rizamat’.The 1635.65 cM high-density map was divided into 19 linkage groups with an average distance of 0.37 cM.Using this map,three significant QTLs for fruit shape index(ShI:ratio of berry length to berry width)identified over three years were mapped onto LG4 and LG5,including one stable QTL on Chr5 with the genomic region of 0.47–1.94 Mb.Combining with gene annotation and expression patterns based on RNA-seq data from two contrasting F2 individuals with round and oblong berry(their average ShI was 1.89 and 1.10,respectively)at four developmental stages,four candidate genes were selected from the above QTLs.They were mainly involved in DNA replication,cell wall modification,and phytohormone biosynthesis.Further analysis of RNA-seq data revealed that several important phytohormone synthesis and metabolic pathways were enriched based on differentially expressed genes(DEGs),which was consistent with the results of QTL mapping for genes related to plant hormone biosynthesis in the F2 population.Furthermore,a comparison of plant hormone content showed that there were significant differences in IAA and tZ content between the two contrasting F2 individuals at different developmental stages.Our findings provide molecular insights into the genetic variation in grape berry shape.Stable QTLs and their tightly linked markers offer the possibility of marker-assisted selection to accelerate berry shape breeding.

Cost-effective low-coverage whole-genome sequencing assay for the risk stratification of gastric cancer

BACKGROUND Gastric cancer(GC), a multifactorial disease, is caused by pathogens, such as Helicobacter pylori(H. pylori) and Epstein-Barr virus(EBV), and genetic components.AIM To investigate microbiomes and host genome instability by cost-effective,low-coverage wholegenome sequencing,as biomarkers for GC subtyping.METHODS Samples from 40 GC patients were collected from Taizhou Hospital,Zhejiang Province,affiliated with Wenzhou Medical University.DNA from the samples was subjected to low-coverage wholegenome sequencing with a median genome coverage of 1.86×(range:1.03×to 3.17×) by Illumina×10,followed by copy number analyses using a customized bioinformatics workflow ultrasensitive chromosomal aneuploidy detector.RESULTS Of the 40 GC samples,20 (50%) were found to be enriched with microbiomes.EBV DNA was detected in 5 GC patients (12.5%).H.pylori DNA was found in 15 (37.5%) patients.The other 20(50%) patients were found to have relatively higher genomic instability.Copy number amplifications of the oncogenes,ERBB2 and KRAS,were found in 9 (22.5%) and 7 (17.5%) of the GC samples,respectively.EBV enrichment was found to be associated with tumors in the gastric cardia and fundus.H.pylori enrichment was found to be associated with tumors in the pylorus and antrum.Tumors with elevated genomic instability showed no localization and could be observed in any location.Additionally,H.pylori-enriched GC was found to be associated with the Borrmann type Ⅱ/Ⅲ and gastritis history.EBV-enriched GC was not associated with gastritis.No statistically significant correlation was observed between genomic instability and gastritis.Furthermore,these three different molecular subtypes showed distinct survival outcomes (P=0.019).EBV-positive tumors had the best prognosis,whereas patients with high genomic instability (CIN+) showed the worst survival.Patients with H.pylori infection showed intermediate prognosis compared with the other two subtypes.CONCLUSION Thus,using low-coverage whole-genome sequencing,GC can be classified into three categories based on disease etiology;this classification may prove useful for GC diagnosis and precision medicine.

Population genetics of marmosets in Asian primate research centers and loci associated with epileptic risk revealed by whole-genome sequencing

The common marmoset(Callithrix jacchus)has emerged as a valuable nonhuman primate model in biomedical research with the recent release of high-quality reference genome assemblies.Epileptic marmosets have been independently reported in two Asian primate research centers.Nevertheless,the population genetics within these primate centers and the specific genetic variants associated with epilepsy in marmosets have not yet been elucidated.Here,we characterized the genetic relationships and risk variants for epilepsy in 41 samples from two epileptic marmoset pedigrees using whole-genome sequencing.We identified 14558184 single nucleotide polymorphisms(SNPs)from the 41 samples and found higher chimerism levels in blood samples than in fingernail samples.Genetic analysis showed fourth-degree of relatedness among marmosets at the primate centers.In addition,SNP and copy number variation(CNV)analyses suggested that the WW domain-containing oxidoreductase(WWOX)and Tyrosine-protein phosphatase nonreceptor type 21(PTPN21)genes may be associated with epilepsy in marmosets.Notably,KCTD18-like gene deletion was more common in epileptic marmosets than control marmosets.This study provides valuable population genomic resources for marmosets in two Asian primate centers.Genetic analyses identified a reasonable breeding strategy for genetic diversity maintenance in the two centers,while the case-control study revealed potential risk genes/variants associated with epilepsy in marmosets.

Whole-genome sequencing study to identify candidate markers indicating susceptibility to type 2 diabetes in Bama miniature pigs

Background:Hundreds of single-nucleotide polymorphism(SNP)sites have been found to be potential genetic markers of type 2 diabetes mellitus(T2DM).However,SNPs related to T2DM in minipigs have been less reported.This study aimed to screen the T2DM-susceptible candidate SNP loci in Bama minipigs so as to improve the success rate of the minipig T2DM model.Methods:The genomic DNAs of three Bama minipigs with T2DM,six sibling lowsusceptibility minipigs with T2DM,and three normal control minipigs were compared by whole-genome sequencing.The T2DM Bama minipig-specific loci were obtained,and their functions were annotated.Meanwhile,the Biomart software was used to perform homology alignment with T2DM-related loci obtained from the human genome-wide association study to screen candidate SNP markers for T2DM in Bama miniature pigs.Results:Whole-genome resequencing detected 6960 specific loci in the minipigs with T2DM,and 13 loci corresponding to 9 diabetes-related genes were selected.Further,a set of 122 specific loci in 69 orthologous genes of human T2DM candidate genes were obtained in the pigs.Collectively,a batch of T2DM-susceptible candidate SNP markers in Bama minipigs,covering 16 genes and 135 loci,was established.Conclusions:Whole-genome sequencing and comparative genomics analysis of the orthologous genes in pigs that corresponded to the human T2DM-related variant loci successfully screened out T2DM-susceptible candidate markers in Bama miniature pigs.Using these loci to predict the susceptibility of the pigs before constructing an animal model of T2DM may help to establish an ideal animal model.

Whole-genome Sequencing Reveals Autooctoploidy in Chinese Sturgeon and Its Evolutionary Trajectories

The order Acipenseriformes,which includes sturgeons and paddlefishes,represents“living fossils”with complex genomes that are good models for understanding whole-genome duplication(WGD)and ploidy evolution in fishes.Here,we sequenced and assembled the first high-quality chromosome-level genome for the complex octoploid Acipenser sinensis(Chinese sturgeon),a critically endangered species that also represents a poorly understood ploidy group in Acipenseriformes.Our results show that A.sinensis is a complex autooctoploid species containing four kinds of octovalents(8n),a hexavalent(6n),two tetravalents(4n),and a divalent(2n).An analysis taking into account delayed rediploidization reveals that the octoploid genome composition of Chinese sturgeon results from two rounds of homologous WGDs,and further provides insights into the timing of its ploidy evolution.This study provides the first octoploid genome resource of Acipenseriformes for understanding ploidy compositions and evolutionary trajectories of polyploid fishes.

Whole-genome resequencing of Hu sheep identifies candidate genes associated with agronomic traits

The phenotypic diversity resulting from artificial or natural selection of sheep has made a significant contribution to human civilization.Hu sheep are a local sheep breed unique to China with high reproductive rates and rapid growth.Genomic selection signatures have been widely used to investigate the genetic mechanisms underlying phenotypic variation in livestock.Here,we conduct whole-genome sequencing of 207 Hu sheep and compare them with the wild ancestors of domestic sheep(Asiatic mouflon)to investigate the genetic characteristics and selection signatures of Hu sheep.Based on six signatures of selection approaches,we detect genomic regions containing genes related to reproduction(BMPR1B,BMP2,PGFS,CYP19,CAMK4,GGT5,and GNAQ),vision(ALDH1A2,SAG,and PDE6B),nervous system(NAV1),and immune response(GPR35,SH2B2,PIK3R3,and HRAS).Association analysis with a population of 1299 Hu sheep reveals that those missense mutations in the GPR35(GPR35 g.952651 A>G;GPR35 g.952496 C>T)and NAV1(NAV1 g.84216190 C>T;NAV1 g.84227412 G>A)genes are significantly associated(P<0.05)with immune and growth traits in Hu sheep,respectively.This research offers unique insights into the selection characteristics of Hu sheep and facilitates further genetic improvement and molecular investigations.

Whole-genome sequencing identifies functional genes for environmental adaptation in Chinese sheep

Sheep(Ovis aries),among the first domesticated species,are now globally widespread and exhibit remarkable adaptability to diverse environments.In this study,we perform whole-genome sequencing of266 animals from 18 distinct Chinese sheep populations,each displaying unique phenotypes indicative of adaptation to varying environmental conditions.Integrating 131 environmental factors with single nucleotide polymorphism variations,we conduct a comprehensive genetic-environmental association analysis.This analysis identifies 35 key genes likely integral to the environmental adaptation of sheep.The functions of these genes include fat tail formation(HOXA10,HOXA11,JAZF1),wool characteristics(FER,FGF5,MITF,PDE4B),horn phenotypes(RXFP2),reproduction(HIBADH,TRIM71,C6H4orf22),and growth traits(ADGRL3,TRHDE).Notably,we observe a significant correlation between the frequency of missense mutations in the PAPSS2 and RXFP2 genes and variations in altitude.Our study reveals candidate genes for adaptive variation in sheep and demonstrates the diversity in how sheep adapt to their environment.

Whole-genome sequencing identifies novel genes for autism in Chinese trios

Autism spectrum disorder(ASD)is a neurodevelopmental disorder with high genetic heritability but heterogeneity.Fully understanding its genetics requires whole-genome sequencing(WGS),but the ASD studies utilizing WGS data in Chinese population are limited.In this study,we present a WGS study for 334 individuals,including 112 ASD patients and their non-ASD parents.We identified 146 de novo variants in coding regions in 85 cases and 60 inherited variants in coding regions.By integrating these variants with an association model,we identified 33 potential risk genes(P<0.001)enriched in neuron and regulation related biological process.Besides the well-known ASD genes(SCN2A,NF1,SHANK3,CHD8 etc.),several high confidence genes were highlighted by a series of functional analyses,including CTNND1,DGKZ,LRP1,DDN,ZNF483,NR4A2,SMAD6,INTS1,and MRPL12,with more supported evidence from GO enrichment,expression and network analysis.We also integrated RNA-seq data to analyze the effect of the variants on the gene expression and found 12 genes in the individuals with the related variants had relatively biased expression.We further presented the clinical phenotypes of the proband carrying the risk genes in both our samples and Caucasian samples to show the effect of the risk genes on phenotype.Regarding variants in noncoding regions,a total of 74 de novo variants and 30 inherited variants were predicted as pathogenic with high confidence,which were mapped to specific genes or regulatory features.The number of de novo variants found in patient was significantly associated with the parents’ages at the birth of the child,and gender with trend.We also identified small de novo structural variants in ASD trios.The results in this study provided important evidence for understanding the genetic mechanism of ASD.

Streamlined whole-genome genotyping through NGS-enhanced thermal asymmetric interlaced(TAIL)-PCR

Whole-genome genotyping(WGG)stands as a pivotal element in genomic-assisted plant breeding.Nevertheless,sequencing-based approaches for WGG continue to be costly,primarily owing to the high expenses associated with library preparation and the laborious protocol.During prior development of foreground and background integrated genotyping by sequencing(FBI-seq),we discovered that any sequence-specific primer(SP)inherently possesses the capability to amplify a massive array of stable and reproducible non-specific PCR products across the genome.Here,we further improved FBI-seq by replacing the adapter ligated by Tn5 transposase with an arbitrary degenerate(AD)primer.The protocol for the enhanced FBI-seq unexpectedly mirrors a simplified thermal asymmetric interlaced(TAIL)-PCR,a technique that is widely used for isolation of flanking sequences.However,the improved TAIL-PCR maximizes the primer-template mismatched annealing capabilities of both SP and AD primers.In addition,leveraging of next-generation sequencing enhances the ability of this technique to assay tens of thousands of genome-wide loci for any species.This cost-effective,user-friendly,and powerful WGG tool,which we have named TAIL-PCR by sequencing(TAIL-peq),holds great potential for widespread application in breeding programs,thereby facilitating genome-assisted crop improvement.

Whole-genome sequencing to detect mutations associated with resistance to insecticides and Bt proteins in Spodoptera frugiperda

The fall armyworm(FAW),Spodoptera frugiperda,is a major pest native to the Americas that has recently invaded the Old World.Point mutations in the target-site proteins acetylcholinesterase-1(ace-1),voltage-gated sodium channel(VGSC)and ryanodine receptor(RyR)have been identified in S.frugiperda as major resistance mechanisms to organophosphate,pyrethroid and diamide insecticides respectively.Mutations in the adenosine triphosphate-binding cassette transporter C2 gene(ABCC2)have also been identified to confer resistance to Cry IF protein.In this study,we applied a whole-genome sequencing(WGS)approach to identify point mutations in the target-site genes in 150 FAW individuals collected from China,Malawi,Uganda and Brazil.This approach revealed three amino acid substitutions(A201S,G227A and F290V)of S.frugiperda ace-1,which are known to be associated with organophosphate resistance.The Brazilian population had all three ace-1 point mutations and the 227A allele(mean frequency=0.54)was the most common.Populations from China,Malawi and Uganda harbored two of the three ace-1 point mutations(A201S and F290V)with the 290V allele(0.47-0.58)as the dominant allele.Point mutations in VGSC(T929I,L932F and L1014F)and RyR(I4790M and G4946E)were not detected in any of the 150 individuals.A novel 12-bp insertion mutation in exon 15 of the ABCC2 gene was identified in some of the Brazilian individuals but absent in the invasive populations.Our results not only demonstrate robustness of the WGS-based genomic approach for detection of resistance mutations,but also provide insights for improvement of resistance management tactics in S.frugiperda.

Whole-genome Duplication Reshaped Adaptive Evolution in A Relict Plant Species,Cyclocarya paliurus

Cyclocarya paliurus is a relict plant species that survived the last glacial period and shows a population expansion recently.Its leaves have been traditionally used to treat obesity and diabetes with the well-known active ingredient cyclocaric acid B.Here,we presented three C.paliurus genomes from two diploids with different flower morphs and one haplotype-resolved tetraploid assembly.Comparative genomic analysis revealed two rounds of recent whole-genome duplication events and identified 691 genes with dosage effects that likely contribute to adaptive evolution through enhanced photosynthesis and increased accumulation of triterpenoids.Resequencing analysis of 45 C.paliurus individuals uncovered two bottlenecks,consistent with the known events of environmental changes,and many selectively swept genes involved in critical biological functions,including plant defense and secondary metabolite biosynthesis.We also proposed the biosynthesis pathway of cyclocaric acid B based on multi-omics data and identified key genes,in particular gibberellinrelated genes,associated with the heterodichogamy in C.paliurus species.Our study sheds light on evolutionary history of C.paliurus and provides genomic resources to study the medicinal herbs.

Whole-genome sequencing of monozygotic twins discordant for schizophrenia indicates multiple genetic risk factors for schizophrenia

Schizophrenia is a common disorder with a high heritability, but its genetic architecture is still elusive.We implemented whole-genome sequencing(WGS) analysis of 8 families with monozygotic(MZ) twin pairs discordant for schizophrenia to assess potential association of de novo mutations(DNMs) or inherited variants with susceptibility to schizophrenia. Eight non-synonymous DNMs(including one splicing site) were identified and shared by twins, which were either located in previously reported schizophrenia risk genes(p.V24689 I mutation in TTN, p.S2506 T mutation in GCN1L1, IVS3+1G > T in DOCK1) or had a benign to damaging effect according to in silico prediction analysis. By searching the inherited rare damaging or loss-of-function(LOF) variants and common susceptible alleles from three classes of schizophrenia candidate genes, we were able to distill genetic alterations in several schizophrenia risk genes, including GAD1, PLXNA2, RELN and FEZ1. Four inherited copy number variations(CNVs; including a large deletion at 16p13.11) implicated for schizophrenia were identified in four families, respectively. Most of families carried both missense DNMs and inherited risk variants, which might suggest that DNMs, inherited rare damaging variants and common risk alleles together conferred to schizophrenia susceptibility. Our results support that schizophrenia is caused by a combination of multiple genetic factors, with each DNM/variant showing a relatively small effect size.

Genomic landscapes of Chinese sporadic autism spectrum disordersrevealed by whole-genome sequencing

Autism spectrum disorder (ASD) is a neurodevelopmental disorder with considerable clinical and genetic heterogeneity.In this study,we identified all classes of genomic variants from whole-genome sequencing (WGS) dataset of 32 Chinese trios with ASD,including de novo mutations,inherited variants,copy number variants (CNVs) and genomic structural variants.A higher mutation rate (Poisson test,P<2.2×10^(-16)) in exonic (1.37×10^(-8)) and 3'-UTR regions (1.42×10^(-8)) was revealed in comparison with that of whole genome (1.05×10^(-8)).Using an integrated model,we identified 87 potentially risk genes (P<0.01) from 4832 genes harboring various rare deleterious variants,including CHD8 and NRXN2,implying that the disorders may be in favor to multiple-hit.In particular,frequent rare inherited mutations of several microcephaly-associated genes (ASPM,WDR62,and ZNF335)were found in ASD.In chromosomal structure analyses,we found four de novo CNVs and one de novo chromosomal rearrangement event,including a de novo duplication of UBE3A-containing region at 15q11.2-q13.1,which causes Angelman syndrome and microcephaly,and a disrupted TNR due to de novo chromosomal translocation t (1;5) (q25.1;q33.2).Taken together,our results suggest that abnormalities of centrosomal function and chromatin remodeling of the microcephaly-associated genes may be implicated in pathogenesis of ASD.Adoption of WGS as a new yet efficient technique to illustrate the full genetic spectrum in complex disorders,such as ASD,could provide novel insights into pathogenesis,diagnosis and treatment.