Discovering Single Nucleotide Polymorphisms Regulating Human Gene Expression Using Allele Specific Expression from RNA-seq Data

AbstractDifferential abundance of allelic transcripts in a diploid organism, commonly referred to as allele specific expression (ASE), is a biologically significant phenomenon and can be examined using single nucleotide polymorphisms (SNPs) from RNA-seq. Quantifying ASE aids in our ability to identify and understand cis-regulatory mechanisms that influence gene expression, and thereby assist in identifying causal mutations. This study examines ASE in breast muscle, abdominal fat, and liver of commercial broiler chickens using variants called from a large sub-set of the samples (n = 68). ASE analysis was performed using a custom software called VCF ASE Detection Tool (VADT), which detects ASE of biallelic SNPs using a binomial test. On average ~ 174,000 SNPs in each tissue passed our filtering criteria and were considered informative, of which ~ 24,000 (~ 14%) showed ASE. Of all ASE SNPs, only 3.7% exhibited ASE in all three tissues, with ~ 83% showing ASE specific to a single tissue. When ASE genes (genes containing ASE SNPs) were compared between tissues, the overlap among all three tissues increased to 20.1%. Our results indicate that ASE genes show tissue-specific enrichment patterns, but all three tissues showed enrichment for pathways involved in translation.

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Transcriptome analysis revealed chimeric RNAs, single nucleotide polymorphisms and allele-specific expression in porcine prenatal skeletal muscle

Scientific Reports ◽

10.1038/srep29039 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 7

Author(s):

Yalan Yang ◽

Zhonglin Tang ◽

Xinhao Fan ◽

Kui Xu ◽

Yulian Mu ◽

...

Keyword(s):

Skeletal Muscle ◽

Single Nucleotide Polymorphisms ◽

Transcriptome Analysis ◽

Nucleotide Polymorphisms ◽

Specific Expression ◽

Single Nucleotide ◽

Allele Specific Expression ◽

Chimeric Rnas ◽

Allele Specific

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Single‐Nucleotide Polymorphisms Associated with Symptomatic Infection and Differential Human Gene Expression in Healthy Seropositive Persons Each Implicate the Cytoskeleton, Integrin Signaling, and Oncosuppression in the Pathogenesis of Human Parvovirus B19 Infection

The Journal of Infectious Diseases ◽

10.1086/430950 ◽

2005 ◽

Vol 192 (2) ◽

pp. 276-286 ◽

Cited By ~ 19

Author(s):

Jonathan R. Kerr ◽

Narendra Kaushik ◽

David Fear ◽

Don A. Baldwin ◽

Emile F. Nuwaysir ◽

...

Keyword(s):

Gene Expression ◽

Single Nucleotide Polymorphisms ◽

Human Gene ◽

Parvovirus B19 ◽

Integrin Signaling ◽

Human Parvovirus B19 ◽

Nucleotide Polymorphisms ◽

Symptomatic Infection ◽

Single Nucleotide ◽

Parvovirus B19 Infection

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RNA-Seq Data for Reliable SNP Detection and Genotype Calling: Interest for Coding Variant Characterization and Cis-Regulation Analysis by Allele-Specific Expression in Livestock Species

Frontiers in Genetics ◽

10.3389/fgene.2021.655707 ◽

2021 ◽

Vol 12 ◽

Author(s):

Frédéric Jehl ◽

Fabien Degalez ◽

Maria Bernard ◽

Frédéric Lecerf ◽

Laetitia Lagoutte ◽

...

Keyword(s):

Gene Expression ◽

Call Rate ◽

Rna Seq ◽

Snp Detection ◽

Specific Expression ◽

Genotype Calling ◽

Allele Specific Expression ◽

Livestock Species ◽

Allele Specific ◽

The Impact

In addition to their common usages to study gene expression, RNA-seq data accumulated over the last 10 years are a yet-unexploited resource of SNPs in numerous individuals from different populations. SNP detection by RNA-seq is particularly interesting for livestock species since whole genome sequencing is expensive and exome sequencing tools are unavailable. These SNPs detected in expressed regions can be used to characterize variants affecting protein functions, and to study cis-regulated genes by analyzing allele-specific expression (ASE) in the tissue of interest. However, gene expression can be highly variable, and filters for SNP detection using the popular GATK toolkit are not yet standardized, making SNP detection and genotype calling by RNA-seq a challenging endeavor. We compared SNP calling results using GATK suggested filters, on two chicken populations for which both RNA-seq and DNA-seq data were available for the same samples of the same tissue. We showed, in expressed regions, a RNA-seq precision of 91% (SNPs detected by RNA-seq and shared by DNA-seq) and we characterized the remaining 9% of SNPs. We then studied the genotype (GT) obtained by RNA-seq and the impact of two factors (GT call-rate and read number per GT) on the concordance of GT with DNA-seq; we proposed thresholds for them leading to a 95% concordance. Applying these thresholds to 767 multi-tissue RNA-seq of 382 birds of 11 chicken populations, we found 9.5 M SNPs in total, of which ∼550,000 SNPs per tissue and population with a reliable GT (call rate ≥ 50%) and among them, ∼340,000 with a MAF ≥ 10%. We showed that such RNA-seq data from one tissue can be used to (i) detect SNPs with a strong predicted impact on proteins, despite their scarcity in each population (16,307 SIFT deleterious missenses and 590 stop-gained), (ii) study, on a large scale, cis-regulations of gene expression, with ∼81% of protein-coding and 68% of long non-coding genes (TPM ≥ 1) that can be analyzed for ASE, and with ∼29% of them that were cis-regulated, and (iii) analyze population genetic using such SNPs located in expressed regions. This work shows that RNA-seq data can be used with good confidence to detect SNPs and associated GT within various populations and used them for different analyses as GTEx studies.

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A survey of genetic and epigenetic variation affecting human gene expression

Physiological Genomics ◽

10.1152/physiolgenomics.00163.2003 ◽

2004 ◽

Vol 16 (2) ◽

pp. 184-193 ◽

Cited By ~ 160

Author(s):

Tomi Pastinen ◽

Robert Sladek ◽

Scott Gurd ◽

Alya’a Sammak ◽

Bing Ge ◽

...

Keyword(s):

Gene Expression ◽

Human Gene ◽

Genetic Diseases ◽

Mendelian Inheritance ◽

Monoallelic Expression ◽

Regulatory Sequence ◽

Epigenetic Variation ◽

Nucleotide Polymorphisms ◽

Human Gene Expression ◽

Allele Specific

The identification of human sequence polymorphisms that regulate gene expression is key to understanding human genetic diseases. We report a survey of human genes that demonstrate allelic differences in gene expression, reflecting the presence of putative allele-specific cis-acting factors of either genetic or epigenetic nature. The expression of allelic transcripts in heterozygous samples is assessed directly by relative quantitation of intragenic marker alleles in messenger or heteronuclear RNA derived from cells or tissues. This survey used 193 single-nucleotide polymorphisms (SNPs) from 129 genes expressed in lymphoblastoid cell lines, to identify 23 genes (18%) with common allele-specific transcripts whose expression deviated from the expected equimolar ratio. A subset of these deviations, or “allelic imbalances,” can be observed in multiple samples derived from reference CEPH (“Centre d’Etude du Polymorphisme Humain”) pedigrees and demonstrate a spectrum of patterns of transmission, including cosegregation of allelic skewing across generations compatible with Mendelian inheritance as well as random monoallelic expression for three genes ( IL1A, HTR2A, and FGB). Additional studies for BTN3A2 provide evidence of SNPs and haplotypes in complete linkage disequilibrium with high- and low-expressing transcripts. The pipeline described herein offers tools for efficient identification and characterization of allelic expression allowing identification of regulatory sequence variants as well as epigenetic variation affecting human gene expression.

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Associations Between the Purinergic Receptor P2X7 and Leprosy Disease

Frontiers in Genetics ◽

10.3389/fgene.2021.730991 ◽

2021 ◽

Vol 12 ◽

Author(s):

Rebeka da Conceição Souza ◽

Thaís Louvain de Souza ◽

Cristina dos Santos Ferreira ◽

Letícia Silva Nascimento ◽

Edilbert Pellegrini Nahn ◽

...

Keyword(s):

Single Nucleotide Polymorphisms ◽

Purinergic Receptor ◽

Significant Risk ◽

Healthy Controls ◽

Nucleotide Polymorphisms ◽

Bone Homeostasis ◽

Specific Expression ◽

Single Nucleotide ◽

Leprosy Patients ◽

Allele Specific

Leprosy is an infectious disease still highly prevalent in Brazil, having been detected around 27,863 new cases in 2019. Exposure to Mycobacterium leprae may not be sufficient to trigger the disease, which seems to be influenced by host immunogenetics to determine resistance or susceptibility. The purinergic receptor P2X7 plays a crucial role in immunity, inflammation, neurological function, bone homeostasis, and neoplasia and is associated with several infectious and non-infectious diseases. Here, we first compare the P2RX7 expression in RNA-seq experiments from 16 leprosy cases and 16 healthy controls to establish the magnitude of allele-specific expression for single-nucleotide polymorphisms of the gene P2RX7 and to determine the level of gene expression in healthy and diseased skin. In addition, we also evaluated the association of two P2RX7 single-nucleotide polymorphisms (c.1513A>C/rs3751143 and c.1068A>G/rs1718119) with leprosy risk. The expression of P2RX7 was found significantly upregulated at macrophage cells from leprosy patients compared with healthy controls, mainly in macrophages from lepromatous patients. Significant risk for leprosy disease was associated with loss function of rs3751143 homozygous mutant CC [CC vs. AA: p = 0.001; odds ratio (OR) = 1.676, 95% CI = 1.251–2.247] but not with heterozygous AC (AC vs. AA: p = 0.001; OR = 1.429, 95% CI = 1.260–1.621). Contrary, the polymorphic A allele from the gain function of rs1718119 was associated with protection for the development of leprosy, as observed in the dominant model (AA + AG × GG p = 0.0028; OR = 0.03516; CI = 0.1801–0.6864). So, our results suggest that the functional P2X7 purinergic receptor may exert a key role in the Mycobacterium death inside macrophages and inflammatory response, which is necessary to control the disease.

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Elimination of reference mapping bias reveals robust immune related allele-specific expression in crossbred sheep

10.1101/619122 ◽

2019 ◽

Cited By ~ 1

Author(s):

Mazdak Salavati ◽

Stephen J. Bush ◽

Sergio Palma-Vera ◽

Mary E. B. McCulloch ◽

David A. Hume ◽

...

Keyword(s):

Gene Expression ◽

Complex Traits ◽

Allelic Imbalance ◽

Cell Types ◽

Rna Seq ◽

Specific Expression ◽

Allele Specific Expression ◽

Gene Expression Atlas ◽

Expression Atlas ◽

Allele Specific

AbstractPervasive allelic variation at both gene and single nucleotide level (SNV) between individuals is commonly associated with complex traits in humans and animals. Allele-specific expression (ASE) analysis, using RNA-Seq, can provide a detailed annotation of allelic imbalance and infer the existence of cis-acting transcriptional regulation. However, variant detection in RNA-Seq data is compromised by biased mapping of reads to the reference DNA sequence. In this manuscript we describe an unbiased standardised computational pipeline for allele-specific expression analysis using RNA-Seq data, which we have adapted and developed using tools available under open licence. The analysis pipeline we present is designed to minimise reference bias while providing accurate profiling of allele-specific expression across tissues and cell types. Using this methodology, we were able to profile pervasive allelic imbalance across tissues and cell types, at both the gene and SNV level, in Texel x Scottish Blackface sheep, using the sheep gene expression atlas dataset. ASE profiles were pervasive in each sheep and across all tissue types investigated. However, ASE profiles shared across tissues were limited and instead they tended to be highly tissue-specific. These tissue-specific ASE profiles may underlie the expression of economically important traits and could be utilized as weighted SNVs, for example, to improve the accuracy of genomic selection in breeding programmes for sheep. An additional benefit of the pipeline is that it does not require parental genotypes and can therefore be applied to other RNA-Seq datasets for livestock, including those available on the Functional Annotation of Animal Genomes (FAANG) data portal. This study is the first global characterisation of moderate to extreme ASE in tissues and cell types from sheep. We have applied a robust methodology for ASE profiling, to provide both a novel analysis of the multi-dimensional sheep gene expression atlas dataset, and a foundation for identifying the regulatory and expressed elements of the genome that are driving complex traits in livestock.

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Effects of common FSH receptor single-nucleotide polymorphisms on the follicular fluid hormone profile and the granulosa cell gene expression in human small antral follicles

Reproduction Abstracts ◽

10.1530/repabs.1.p353 ◽

2014 ◽

Author(s):

Tanni Borgbo ◽

Hana Kluckova ◽

Milan MacEk ◽

Jana Chrudimska ◽

Janni V Jeppesen ◽

...

Keyword(s):

Gene Expression ◽

Single Nucleotide Polymorphisms ◽

Follicular Fluid ◽

Fsh Receptor ◽

Nucleotide Polymorphisms ◽

Single Nucleotide ◽

Antral Follicles ◽

Hormone Profile ◽

Cell Gene Expression ◽

Cell Gene

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The role of 25-hydroxyvitamin-D3 and vitamin D receptor gene in human periodontal ligament fibroblasts as response to orthodontic compressive strain: an in vitro study

BMC Oral Health ◽

10.1186/s12903-021-01740-8 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Erika Calvano Küchler ◽

Agnes Schröder ◽

Vinicius Broska Teodoro ◽

Ute Nazet ◽

Rafaela Scariot ◽

...

Keyword(s):

Gene Expression ◽

Vitamin D ◽

Single Nucleotide Polymorphisms ◽

Periodontal Ligament ◽

Compressive Strain ◽

Nucleotide Polymorphisms ◽

Periodontal Ligament Fibroblasts ◽

Single Nucleotide ◽

Cox 2

Abstract Background This study aimed to investigate, if different physiological concentrations of vitamin D (25(OH)D3) and single nucleotide polymorphisms in vitamin D receptor (VDR) gene have an impact on gene expression in human periodontal ligament (hPDL) fibroblasts induced by simulated orthodontic compressive strain. Methods A pool of hPDL fibroblasts was treated in absence or presence of 25(OH)D3 in 3 different concentrations (10, 40 and 60 ng/ml). In order to evaluate the role of single nucleotide polymorphisms in the VDR gene, hPDL fibroblasts from 9 patients were used and treated in absence or presence of 40 ng/ml 25(OH)D3. Each experiment was performed with and without simulated orthodontic compressive strain. Real-time PCR was used for gene expression and allelic discrimination analysis. Relative expression of dehydrocholesterol reductase (DHCR7), Sec23 homolog A, amidohydrolase domain containing 1 (AMDHD1), vitamin D 25-hydroxylase (CYP2R1), Hydroxyvitamin D-1-α hydroxylase, receptor activator of nuclear factor-κB ligand (RANKL), osteoprotegerin (OPG), cyclooxygenase-2 (COX-2) and interleukin-6 (IL6) was assessed. Three single nucleotide polymorphisms in VDR were genotyped. Parametric or non-parametric tests were used with an alpha of 5%. Results RANKL, RANKL:OPG ratio, COX-2, IL-6, DHCR7, CYP2R1 and AMDHD1 were differentially expressed during simulated orthodontic compressive strain (p < 0.05). The RANKL:OPG ratio was downregulated by all concentrations (10 ng/ml, 40 ng/ml and 60 ng/ml) of 25(OH)D3 (mean = 0.96 ± 0.68, mean = 1.61 ± 0.66 and mean = 1.86 ± 0.78, respectively) in comparison to the control (mean 2.58 ± 1.16) (p < 0.05). CYP2R1 gene expression was statistically modulated by the different 25(OH)D3 concentrations applied (p = 0.008). Samples from individuals carrying the GG genotype in rs739837 presented lower VDR mRNA expression and samples from individuals carrying the CC genotype in rs7975232 presented higher VDR mRNA expression (p < 0.05). Conclusions Simulated orthodontic compressive strain and physiological concentrations of 25(OH)D3 seem to regulate the expression of orthodontic tooth movement and vitamin-D-related genes in periodontal ligament fibroblasts in the context of orthodontic compressive strain. Our study also suggests that single nucleotide polymorphisms in the VDR gene regulate VDR expression in periodontal ligament fibroblasts in the context of orthodontic compressive strain.

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