scholarly journals Runs of Homozygosity as Footprints of Selection in the Norik of Muran Horse Genome

2019 ◽  
Vol 67 (5) ◽  
pp. 1165-1170 ◽  
Author(s):  
Nina Moravčíková ◽  
Radovan Kasarda ◽  
Ondrej Kadlečík ◽  
Anna Trakovická ◽  
Marko Halo ◽  
...  
Keyword(s):  
Selection Pressure ◽  
Wide Distribution ◽  
Runs Of Homozygosity ◽  
Protein Coding ◽  
Strong Selection ◽  
Protein Coding Genes ◽  
Horse Genome ◽  
Genome Wide ◽  
Genomic Regions ◽  
Intensive Breeding

The aim of this study was to analyse the genome-wide distribution of runs of homozygosity (ROH) segments in the genome of Norik of Muran horse and to identify the regions under strong selection pressure. Overall, 25 animals genotyped by the GGP Equine70k chip were included in the study. After SNP pruning, 54479 SNPs (75.72%) covering 2.25 Gb of the autosomal genome were retained for scan of ROH segments distribution. The ROHs were present in the genome of all animals and covered in average 13.17% (295.29 Mb) of autosomal genome expressed by the SNP loci. The highest number of ROHs was identified on autosome 1 (404), while the lowest proportion of autosome residing in ROH showed ECA31 (38). The footprints of selection, characterized by SNPs with extreme frequency in ROHs across specific genomic regions, were defined by the top 0.01 percentile of signals. Overall, nine genomic regions located on seven autosomes (3, 6, 9, 11, 15, 23) were identified. The strongest signal of selection showed three autosomes ECA3, ECA9 and ECA11. The protein-coding genes located within these regions suggested that the identified footprints of selection are most likely consequences of intensive breeding for traits of interest during the grading-up process of the Norik of Muran horse.

scholarly journals Tri-methylation of Histone H3 Lysine 4 Facilitates Gene Expression in Ageing Cells

2017 ◽  
Author(s):  
Cristina Cruz ◽  
Monica Della Rosa ◽  
Christel Krueger ◽  
Qian Gao ◽  
Lucy Field ◽  
...  
Keyword(s):  
Gene Expression ◽  
Budding Yeast ◽  
Histone H3 ◽  
Specific Factor ◽  
Protein Coding ◽  
Replicative Lifespan ◽  
Protein Coding Genes ◽  
Genome Wide ◽  
Normal Expression ◽  
Transcriptional Induction

AbstractTranscription of protein coding genes is accompanied by recruitment of COMPASS to promoter-proximal chromatin, which deposits di- and tri-methylation on histone H3 lysine 4 (H3K4) to form H3K4me2 and H3K4me3. Here we determine the importance of COMPASS in maintaining gene expression across lifespan in budding yeast. We find that COMPASS mutations dramatically reduce replicative lifespan and cause widespread gene expression defects. Known repressive functions of H3K4me2 are progressively lost with age, while hundreds of genes become dependent on H3K4me3 for full expression. Induction of these H3K4me3 dependent genes is also impacted in young cells lacking COMPASS components including the H3K4me3-specific factor Spp1. Remarkably, the genome-wide occurrence of H3K4me3 is progressively reduced with age despite widespread transcriptional induction, minimising the normal positive correlation between promoter H3K4me3 and gene expression. Our results provide clear evidence that H3K4me3 is required to attain normal expression levels of many genes across organismal lifespan.

scholarly journals Paternally inherited noncoding structural variants contribute to autism

2017 ◽  
Author(s):  
William M. Brandler ◽  
Danny Antaki ◽  
Madhusudan Gujral ◽  
Morgan L. Kleiber ◽  
Michelle S. Maile ◽  
...  
Keyword(s):  
De Novo ◽  
Fetal Brain ◽  
Wide Distribution ◽  
Autism Spectrum ◽  
Structural Variants ◽  
De Novo Mutations ◽  
Whole Genome Analysis ◽  
Protein Coding ◽  
Genome Wide ◽  
Exome Aggregation Consortium

AbstractThe genetic architecture of autism spectrum disorder (ASD) is known to consist of contributions from gene-disrupting de novo mutations and common variants of modest effect. We hypothesize that the unexplained heritability of ASD also includes rare inherited variants with intermediate effects. We investigated the genome-wide distribution and functional impact of structural variants (SVs) through whole genome analysis (≥30X coverage) of 3,169 subjects from 829 families affected by ASD. Genes that are intolerant to inactivating variants in the exome aggregation consortium (ExAC) were depleted for SVs in parents, specifically within fetal-brain promoters, UTRs and exons. Rare paternally-inherited SVs that disrupt promoters or UTRs were over-transmitted to probands (P = 0.0013) and not to their typically-developing siblings. Recurrent functional noncoding deletions implicate the gene LEO1 in ASD. Protein-coding SVs were also associated with ASD (P = 0.0025). Our results establish that rare inherited SVs predispose children to ASD, with differing contributions from each parent.

scholarly journals Defining the functional significance of intergenic transcribed regions

2017 ◽  
Author(s):  
John P. Lloyd ◽  
Zing Tsung-Yeh Tsai ◽  
Rosalie P. Sowers ◽  
Nicholas L. Panchy ◽  
Shin-Han Shiu
Keyword(s):  
Flowering Plant ◽  
Sequence Structure ◽  
Transcriptional Noise ◽  
Novel Genes ◽  
Protein Coding ◽  
Genome Wide ◽  
Intergenic Regions ◽  
Flowering Plant Species ◽  
Genomic Regions ◽  
Rna Genes

ABSTRACTWith advances in transcript profiling, the presence of transcriptional activities in intergenic regions has been well established. However, whether intergenic expression reflects transcriptional noise or activity of novel genes remains unclear. We identified intergenic transcribed regions (ITRs) in 15 diverse flowering plant species and found that the amount of intergenic expression correlates with genome size, a pattern that could be expected if intergenic expression is largely nonfunctional. To further assess the functionality of ITRs, we first built machine learning classifiers using Arabidopsis thaliana as a model that accurately distinguish functional sequences (phenotype genes) and likely nonfunctional ones (pseudogenes and unexpressed intergenic regions) by integrating 93 biochemical, evolutionary, and sequence-structure features. Next, by applying the models genome-wide, we found that 4,427 ITRs (38%) and 796 annotated ncRNAs (44%) had features significantly similar to benchmark protein-coding or RNA genes and thus were likely parts of functional genes. Approximately 60% of ITRs and ncRNAs were more similar to nonfunctional sequences and were likely transcriptional noise. The predictive framework established here provides not only a comprehensive look at how functional, genic sequences are distinct from likely nonfunctional ones, but also a new way to differentiate novel genes from genomic regions with noisy transcriptional activities.

scholarly journals GENOME-WIDE DISTRIBUTION OF AUTOZYGOSITY ISLANDS IN SLOVAK WARMBLOOD HORSE

AGROFOR ◽  
2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Nina MORAVČÍKOVÁ ◽  
Radovan KASARDA ◽  
Marko HALO ◽  
Ondrej KADLEČÍK ◽  
Anna TRAKOVICKÁ ◽  
...  
Keyword(s):  
Genetic Structure ◽  
Allele Frequency ◽  
Selection Pressure ◽  
Wide Distribution ◽  
Call Rate ◽  
Major Fraction ◽  
Autosomal Snps ◽  
The Past ◽  
Genome Wide ◽  
Recent Selection

The objective of this study was to estimate the distribution of autozygosity islands represented by homozygous segments (ROHs) in the genome of the Slovak Warmblood horse. The Slovak Warmblood is a very efficient breed with the excellent characteristics of a sport horse. The study included 37 animals that were genotyped by GGP Equine70k chip (71,947 SNPs). Only animals (36) and autosomal SNPs (62,439) with call rate >90% and minor allele frequency >1% were included in subsequent analyses. The homozygous segments were defined as stretches with minimum 15 consecutive homozygous SNPs of >500 kb with minimum density 1 SNP per 100 kb and maximum gap between markers of 1,000 kb. The heterozygous or missing calls were not accepted. The analysis indicated in total of 8,501 autozygosity islands in the genome of the Slovak Warmblood horse. The majority of identified segments (85.42%) were most likely derived from the remote ancestors in the past. Only 0.15% of detected segments resulted from the recent selection events affecting the genetic structure of studied population. The proportion of segments varied across chromosomes. The major fraction of autosome residing in ROH was found on ECA1 (8.30%), while ECA31 showed the lowest ROH coverage. The scan for overlapping homozygous segments shared by more than 50 % of animals demonstrated that the ECA6 autosome may be under strong selection pressure. Inside those selection signals, several genes were identified including them associated with immunity and reproduction.

scholarly journals Protein-Coding Genes of Helicobacter pylori Predominantly Present Purifying Selection though Many Membrane Proteins Suffer from Selection Pressure: A Proposal to Analyze Bacterial Pangenomes

Genes ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 377
Author(s):  
Alejandro Rubio ◽  
Antonio Pérez-Pulido
Keyword(s):  
Helicobacter Pylori ◽  
Membrane Proteins ◽  
Selection Pressure ◽  
Purifying Selection ◽  
Protein Coding ◽  
Evolutionary Selection ◽  
Protein Coding Genes ◽  
The Core ◽  
Genes Encoding ◽  
Selection For

The current availability of complete genome sequences has allowed knowing that bacterial genomes can bear genes not present in the genome of all the strains from a specific species. So, the genes shared by all the strains comprise the core of the species, but the pangenome can be much greater and usually includes genes appearing in one only strain. Once the pangenome of a species is estimated, other studies can be undertaken to generate new knowledge, such as the study of the evolutionary selection for protein-coding genes. Most of the genes of a pangenome are expected to be subject to purifying selection that assures the conservation of function, especially those in the core group. However, some genes can be subject to selection pressure, such as genes involved in virulence that need to escape to the host immune system, which is more common in the accessory group of the pangenome. We analyzed 180 strains of Helicobacter pylori, a bacterium that colonizes the gastric mucosa of half the world population and presents a low number of genes (around 1500 in a strain and 3000 in the pangenome). After the estimation of the pangenome, the evolutionary selection for each gene has been calculated, and we found that 85% of them are subject to purifying selection and the remaining genes present some grade of selection pressure. As expected, the latter group is enriched with genes encoding for membrane proteins putatively involved in interaction to host tissues. In addition, this group also presents a high number of uncharacterized genes and genes encoding for putative spurious proteins. It suggests that they could be false positives from the gene finders used for identifying them. All these results propose that this kind of analyses can be useful to validate gene predictions and functionally characterize proteins in complete genomes.

scholarly journals Genome-Wide Patterns of Homozygosity and Relevant Characterizations on the Population Structure in Piétrain Pigs

Genes ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 577
Author(s):  
Huiwen Zhan ◽  
Saixian Zhang ◽  
Kaili Zhang ◽  
Xia Peng ◽  
Shengsong Xie ◽  
...  
Keyword(s):  
Linkage Disequilibrium ◽  
Population Size ◽  
Effective Population Size ◽  
Average Length ◽  
The Other ◽  
Runs Of Homozygosity ◽  
Effective Population ◽  
Inbreeding Coefficients ◽  
Genome Wide ◽  
Genomic Regions

Investigating the patterns of homozygosity, linkage disequilibrium, effective population size and inbreeding coefficients in livestock contributes to our understanding of the genetic diversity and evolutionary history. Here we used Illumina PorcineSNP50 Bead Chip to identify the runs of homozygosity (ROH) and estimate the linkage disequilibrium (LD) across the whole genome, and then predict the effective population size. In addition, we calculated the inbreeding coefficients based on ROH in 305 Piétrain pigs and compared its effect with the other two types of inbreeding coefficients obtained by different calculation methods. A total of 23,434 ROHs were detected, and the average length of ROH per individual was about 507.27 Mb. There was no regularity on how those runs of homozygosity distributed in genome. The comparisons of different categories suggested that the formation of long ROH was probably related with recent inbreeding events. Although the density of genes located in ROH core regions is lower than that in the other genomic regions, most of them are related with Piétrain commercial traits like meat qualities. Overall, the results provide insight into the way in which ROH is produced and the identified ROH core regions can be used to map the genes associated with commercial traits in domestic animals.

scholarly journals Genome-Wide Scan for Runs of Homozygosity Identifies Candidate Genes Related to Economically Important Traits in Chinese Merino

Animals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 524 ◽  
Author(s):  
Sangang He ◽  
Jiang Di ◽  
Bing Han ◽  
Lei Chen ◽  
Mingjun Liu ◽  
...  
Keyword(s):  
Candidate Genes ◽  
Average Length ◽  
Inbreeding Coefficient ◽  
Whole Genome ◽  
Runs Of Homozygosity ◽  
Genotyping Array ◽  
Genome Region ◽  
Genome Wide ◽  
Genomic Regions ◽  
Genome Wide Scan

In this study, we estimated the number, length, and frequency of runs of homozygosity (ROH) in 635 Chinese Merino and identified genomic regions with high ROH frequency using the OvineSNP50 whole-genome genotyping array. A total of 6039 ROH exceeding 1 Mb were detected in 634 animals. The average number of ROH in each animal was 9.23 and the average length was 5.87 Mb. Most of the ROH were less than 10 Mb, accounting for 88.77% of the total number of detected ROH. In addition, Ovies aries chromosome (OAR) 21 and OAR3 exhibited the highest and lowest coverage of chromosomes by ROH, respectively. OAR1 displayed the highest number of ROH, while the lowest number of ROH was found on OAR24. An inbreeding coefficient of 0.023 was calculated from ROH greater than 1 Mb. Thirteen regions on chromosomes 1, 2, 3, 5, 6, 10, 11, and 16 were found to contain ROH hotspots. Within the genome regions of OAR6 and OAR11, NCAPG/LCORL, FGF11 and TP53 were identified as the candidate genes related to body size, while the genome region of OAR10 harbored RXFP2 gene responsible for the horn trait. These findings indicate the adaptive to directional trait selection in Chinese Merino.

scholarly journals Comparative analysis of the characteristics of Haplorchis taichui mitochondrial genome with Metagonimus yokogawai and its ribosomal transcription unit with H. pumilio (family Heterophyidae)

2021 ◽  
Vol 19 (1) ◽  
pp. 69-84
Author(s):  
Le Thi Viet Ha ◽  
Nguyen Thi Khue ◽  
Dong Van Quyen ◽  
Le Thanh Hoa
Keyword(s):  
Mitochondrial Genome ◽  
Complete Mitochondrial Genome ◽  
Transcription Unit ◽  
Protein Coding ◽  
5.8S Rdna ◽  
Protein Coding Genes ◽  
Repeat Units ◽  
Genomic Gene ◽  
Haplorchis Taichui ◽  
Genomic Regions

Minute intestinal flukes, Haplorchis taichui and H. pumilio, belong to the family Heterophyidae (Trematoda: Platyhelminthes), which have been studied very limited, especially the molecular markers of the mitochondrial genomes (mtDNA) and the ribosome transcription units (rTU or rDNA). We have obtained the complete mitochondrial genome of H. taichui and the coding part of ribosome transcription unit of H. taichui and H. pumilio of Vietnam. Nucleotide and amino acid data were compared between H. taichui and Metagonimus yokogawai for genomic/gene composition, codon usage (skew/skewness), and tandem repeat units (TRU). The complete mtDNA of H. taichui (strain Htai-QT3-VN) with the length of 15,120 bp and M. yokogawai (15,258 bp; Korea; KC330755) contains 36 genes, including 12 protein-coding genes (cox1, cox2, cox3, nad1, nad2, nad3, nad4L, nad4, nad5, nad6, atp6 and cob), 2 ribosomal RNA genes (rRNA); 22 transfer RNA (tRNA or trn) and a noncoding region (NCR) between trnE and trnG, divided into 2 sub-regions containing 5  TRUs (182–183 bp/TRU). H. taichui (Vietnam and Laos) uses A = 19.56%, T = 39.71%, G = 28.34%, C = 12.39% (A + T is 59.27% ​​and G + C is 40.73%) for mtDNA construction, whose skew/skewness value at A+T is negative (–0,340) and G+C is positive (0.392); for 12 protein-coding genes (PCGs) is similar; but for the mito-ribosomal genes (MRGs, of 16S/rrnL and 12S/rrnS) it is less for A+T (57.22%) and more for G+C (42.78%). M. yokogawai had lower A+T (mtDNA/55.68%; PCGs/55.96%; MRGs/54.15%) and higher G+C usage rate than H. taichui. H. taichui of Vietnam and Laos has 10,164 bp encoding for 3,376 amino acids to construct 12 PCGs with the mostly used codons as Phenylalanine (Phe-TTT) and Leucine (Leu-TTG), and the leastly used codonsas Glutamine (Gln-CAA), Arginine (Arg-CGC). Additional condon, Thr-ACA/ACC can be added as the least used in M. yokogawai. The rTU (from 5 '18S to 3' 28S) of H. taichui (7,268 bp) and H. pumilio (7,416 bp) were identified with 5 genomic regions including 18S rDNA, ITS1, 5.8S rDNA, ITS2 and 28S rDNA. The 18S and 5.8S genes of both species were of the same length (1,992 bp for 18S, 160 bp for 5.8S), but different for 28S genes (3,875 bp for H. taichui and 3,870 bp for H. pumilio). ITS1 in H. taichui (797 bp) and ITS2 in H. pumilio (280 bp) do not contain TRUs, whilst ITS1 in H. pumilio (1,106 bp) contains 5 TRUs(136 bp for 3 TRU and 116 bp for 2 TRUs); and ITS2 in H. taichui (444 bp) contain 3 TRUs (83–85 bp/each).

scholarly journals GARFIELD - GWAS Analysis of Regulatory or Functional Information Enrichment with LD correction

2016 ◽  
Author(s):  
Valentina Iotchkova ◽  
Graham R.S. Ritchie ◽  
Matthias Geihs ◽  
Sandro Morganella ◽  
Josine L. Min ◽  
...  
Keyword(s):  
Association Studies ◽  
R Package ◽  
Genome Wide Association Studies ◽  
Protein Coding ◽  
Functional Annotations ◽  
Novel Approach ◽  
Genome Wide ◽  
Functional Consequences ◽  
Genomic Regions ◽  
Coding Variants

Loci discovered by genome-wide association studies (GWAS) predominantly map outside protein-coding genes. The interpretation of functional consequences of non-coding variants can be greatly enhanced by catalogs of regulatory genomic regions in cell lines and primary tissues. However, robust and readily applicable methods are still lacking to systematically evaluate the contribution of these regions to genetic variation implicated in diseases or quantitative traits. Here we propose a novel approach that leverages GWAS findings with regulatory or functional annotations to classify features relevant to a phenotype of interest. Within our framework, we account for major sources of confounding that current methods do not offer. We further assess enrichment statistics for 27 GWAS traits within regulatory regions from the ENCODE and Roadmap projects. We characterise unique enrichment patterns for traits and annotations, driving novel biological insights. The method is implemented in standalone software and R package to facilitate its application by the research community.

Sign in / Sign up

Export Citation Format

Share Document