Genome-wide Association Testing Research Articles

Genome-wide association testing beyond SNPs.

Decades of genetic association testing in human cohorts have provided important insights into the genetic architecture and biological underpinnings of complex traits and diseases. However, for certain traits, genome-wide association studies (GWAS) for common SNPs are approaching signal saturation, which underscores the need to explore other types of genetic variation to understand the genetic basis of traits and diseases. Copy number variation (CNV) is an important source of heritability that is well known to functionally affect human traits. Recent technological and computational advances enable the large-scale, genome-wide evaluation of CNVs, with implications for downstream applications such as polygenic risk scoring and drug target identification. Here, we review the current state of CNV-GWAS, discuss current limitations in resource infrastructure that need to be overcome to enable the wider uptake of CNV-GWAS results, highlight emerging opportunities and suggest guidelines and standards for future GWAS for genetic variation beyond SNPs at scale.

Genetic and functional analysis of Raynaud’s syndrome implicates loci in vasculature and immunity

Raynaud's syndrome is a dysautonomia where exposure to cold causes vasoconstriction and hypoxia, particularly in the extremities. We performed meta-analysis in four cohorts and discovered eight loci (ADRA2A, IRX1, NOS3, ACVR2A, TMEM51, PCDH10-DT, HLA, and RAB6C) where ADRA2A, ACVR2A, NOS3, TMEM51, and IRX1 co-localized with expression quantitative trait loci (eQTLs), particularly in distal arteries. CRISPR gene editing further showed that ADRA2A and NOS3 loci modified gene expression and in situ RNAscope clarified the specificity of ADRA2A in small vessels and IRX1 around small capillaries in the skin. A functional contraction assay in the cold showed lower contraction in ADRA2A-deficient and higher contraction in ADRA2A-overexpressing smooth muscle cells. Overall, our study highlights the power of genome-wide association testing with functional follow-up as a method to understand complex diseases. The results indicate temperature-dependent adrenergic signaling through ADRA2A, effects at the microvasculature by IRX1, endothelial signaling by NOS3, and immune mechanisms by the HLA locus in Raynaud's syndrome.

YQTL Pipeline: A structured computational workflow for large scale quantitative trait loci discovery and downstream visualization.

Quantitative trait loci (QTL) denote regions of DNA whose variation is associated with variations in quantitative traits. QTL discovery is a powerful approach to understand how changes in molecular and clinical phenotypes may be related to DNA sequence changes. However, QTL discovery analysis encompasses multiple analytical steps and the processing of multiple input files, which can be laborious, error prone, and hard to reproduce if performed manually. To facilitate and automate large-scale QTL analysis, we developed the yQTL Pipeline, where the 'y' indicates the dependent quantitative variable being modeled. Prior to the association test, the pipeline supports the calculation or the direct input of pre-defined genome-wide principal components and genetic relationship matrix when applicable. User-specified covariates can also be provided. Depending on whether familial relatedness exists among the subjects, genome-wide association tests will be performed using either a linear mixed-effect model or a linear model. The options to run an ANOVA model or testing the interaction with a covariate are also available. Using the workflow management tool Nextflow, the pipeline parallelizes the analysis steps to optimize run-time and ensure results reproducibility. In addition, a user-friendly R Shiny App is developed to facilitate result visualization. It can generate Manhattan and Miami plots of phenotype traits, genotype-phenotype boxplots, and trait-QTL connection networks. We applied the yQTL Pipeline to analyze metabolomics profiles of blood serum from the New England Centenarians Study (NECS) participants. A total of 9.1M SNPs and 1,052 metabolites across 194 participants were analyzed. Using a p-value cutoff 5e-8, we found 14,983 mQTLs associated with 312 metabolites. The built-in parallelization of our pipeline reduced the run time from ~90 min to ~26 min. Visualization using the R Shiny App revealed multiple mQTLs shared across multiple metabolites. The yQTL Pipeline is available with documentation on GitHub at https://github.com/montilab/yQTLpipeline.

Genome-Wide Association Study and Identification of Candidate Genes Associated with Seed Number per Pod in Soybean.

Soybean (Glycine max [L.] Merr.) is one of the primary sources of plant protein and oil for human foods, animal feed, and industrial processing. The seed number per pod generally varies from one to four and is an important component of seed number per unit area and seed yield. We used natural variation in 264 landraces and improved cultivars or lines to identify candidate genes involved in the regulation of seed number per pod in soybean. Genome-wide association tests revealed 65 loci that are associated with seed number per pod trait. Among them, 11 could be detected in multiple environments. Candidate genes were identified for seed number per pod phenotype from the most significantly associated loci, including a gene encoding protein argonaute 4, a gene encoding histone acetyltransferase of the MYST family 1, a gene encoding chromosome segregation protein SMC-1 and a gene encoding exocyst complex component EXO84A. In addition, plant hormones were found to be involved in ovule and seed development and the regulation of seed number per pod in soybean. This study facilitates the dissection of genetic networks underlying seed number per pod in soybean, which will be useful for the genetic improvement of seed yield in soybean.

Functional annotation with expression validation identifies novel metastasis-relevant genes from post-GWAS risk loci in sporadic colorectal carcinomas

BackgroundColorectal cancer (CRC) is the third highest incidence cancer and is the leading cause of cancer mortality worldwide. Metastasis to distal organ is the major cause of cancer mortality. However,...

Genome-Wide Association Study of Blood Mercury in European Pregnant Women and Children.

Mercury has high industrial utility and is present in many products, and environmental contamination and occupational exposure are widespread. There are numerous biological systems involved in the absorption, metabolism, and excretion of Hg, and it is possible that some systems may be impacted by genetic variation. If so, genotype may affect tissue concentrations of Hg and subsequent toxic effects. Genome-wide association testing was performed on blood Hg samples from pregnant women of the Avon Longitudinal Study of Parents and Children (n = 2893) and children of the Human Early Life Exposome (n = 1042). Directly-genotyped single-nucleotide polymorphisms (SNPs) were imputed to the Haplotype Reference Consortium r1.1 panel of whole genotypes and modelled againstlog-transformed Hg. Heritability was estimated using linkage disequilibrium score regression. The heritability of Hg was estimated as 24.0% (95% CI: 16.9% to 46.4%) in pregnant women, but could not be determined in children. There were 16 SNPs associated with Hg in pregnant women above a suggestive p-value threshold (p < 1 × 10-5), and 21 for children. However, no SNP passed this threshold in both studies, and none were genome-wide significant (p < 5 × 10-8). SNP-Hg associations were highly discordant between women and children, and this may reflect differences in metabolism, a gene-age interaction, or dose-response effects. Several suggestive variants had plausible links to Hg metabolism, such as rs146099921 in metal transporter SLC39A14, and two variants (rs28618224, rs7154700) in potassium voltage-gated channel genes. The findings would benefit from external validation, as suggestive results may contain both true associations and false positives.

Review: Genetic mutations affecting bull fertility.

Cattle are a well-suited "model organism" to study the genetic underpinnings of variation in male reproductive performance. The adoption of artificial insemination and genomic prediction in many cattle breeds provide access to microarray-derived genotypes and repeated measurements for semen quality and insemination success in several thousand bulls. Similar-sized mapping cohorts with phenotypes for male fertility are not available for most other species precluding powerful association testing. The repeated measurements of the artificial insemination bulls' semen quality enable the differentiation between transient and biologically relevant trait fluctuations, and thus, are an ideal source of phenotypes for variance components estimation and genome-wide association testing. Genome-wide case-control association testing involving bulls with either aberrant sperm quality or low insemination success revealed several causal recessive loss-of-function alleles underpinning monogenic reproductive disorders. These variants are routinely monitored with customised genotyping arrays in the male selection candidates to avoid the use of subfertile or infertile bulls for artificial insemination and natural service. Genome-wide association studies with quantitative measurements of semen quality and insemination success revealed quantitative trait loci for male fertility, but the underlying causal variants remain largely unknown. Moreover, these loci explain only a small part of the heritability of male fertility. Integrating genome-wide association studies with gene expression and other omics data from male reproductive tissues is required for the fine-mapping of candidate causal variants underlying variation in male reproductive performance in cattle.

Genome-wide association testing in malaria studies in the presence of overdominance

BackgroundIn human genetics, heterozygote advantage (heterosis) has been detected in studies that focused on specific genes but not in genome-wide association studies (GWAS). For example, heterosis is believed to confer resistance to certain strains of malaria in patients heterozygous for the sickle-cell gene, haemoglobin S (HbS). Yet the power of allelic tests can be substantially diminished by heterosis. Since GWAS (and haplotype-associations) also utilize allelic tests, it is unclear to what degree GWAS could underachieve because heterosis is ignored.MethodsIn this study, a two-step approach to genetic association testing in malaria studies in a GWAS setting that may enhance the power of the tests was proposed, by identifying the underlying genetic model first before applying the association tests. Generalized linear models for dominant, recessive, additive, and heterotic effects were fitted and model selection was performed. This was achieved via tests of significance using the MAX and allelic tests, noting the minimum p-values across all the models and the proportion of tests that a given genetic model was deemed the best. An example dataset, based on 17 SNPs, from a robust genetic association study and simulated genotype datasets, were used to illustrate the method. Case–control genotype data on malaria from Kenya and Gambia were used for validation.Results and conclusionResults showed that the allelic test returned some false negatives under the heterosis model, suggesting reduced power in testing genetic association. Disparities were observed for some chromosomes in the Kenyan and Gambian datasets, including the sex chromosomes. Thus, GWAS and haplotype associations should be treated with caution, unless the underlying genetic model had been determined.

Genome assembly and association tests identify interacting loci associated with vigor, precocity, and sex in interspecific pistachio rootstocks.

Understanding the basis of hybrid vigor remains a key question in crop breeding and improvement, especially for rootstock development where F1 hybrids are extensively utilized. Full-sibling UCB-1 F1 seedling rootstocks are widely planted in commercial pistachio orchards that are generated by crossing 2 highly heterozygous outbreeding parental trees of Pistacia atlantica (female) and P. integerrima (male). This results in extensive phenotypic variability, prompting costly removal of low-yielding small trees. To identify the genetic basis of this variability, we assembled chromosome-scale genome assemblies of the parental trees of UCB-1. We genotyped 960 UCB-1 trees in an experimental orchard for which we also collected multiyear phenotypes. We genotyped an additional 1,358 rootstocks in 6 commercial pistachio orchards and collected single-year tree-size data. Genome-wide single marker association tests identified loci associated with tree size and shape, sex, and precocity. In the experimental orchard, we identified multiple trait-associated loci and a strong candidate for ZZ/ZW sex chromosomes. We found significant marker associations unique to different traits and to early vs late phenotypic measures of the same trait. We detected 2 loci strongly associated with rootstock size in commercial orchards. Pseudo-testcross classification of markers demonstrated that the trait-associated alleles for each locus were segregating in the gametes of opposite parents. These 2 loci interact epistatically to generate the bimodal distribution of tree size with undesirable small trees observed by growers. We identified candidate genes within these regions. These findings provide a foundational resource for marker development and genetic selection of vigorous pistachio UCB-1 rootstock.

Coronavirus Host Genomics Study: South Africa (COVIGen-SA).

Host genetic factors are known to modify the susceptibility, severity, and outcomes of COVID-19 and vary across populations. However, continental Africans are yet to be adequately represented in such studies despite the importance of genetic factors in understanding Africa's response to the pandemic. We describe the development of a research resource for coronavirus host genomics studies in South Africa known as COVIGen-SA—a multicollaborator strategic partnership designed to provide harmonised demographic, clinical, and genetic information specific to Black South Africans with COVID-19. Over 2,000 participants have been recruited to date. Preliminary results on 1,354 SARS-CoV-2 positive participants from four participating studies showed that 64.7% were female, 333 had severe disease, and 329 were people living with HIV. Through this resource, we aim to provide insights into host genetic factors relevant to African-ancestry populations, using both genome-wide association testing and targeted sequencing of important genomic loci. This project will promote and enhance partnerships, build skills, and develop resources needed to address the COVID-19 burden and associated risk factors in South African communities.

To stripe or not to stripe: the origin of a novel foliar pigmentation pattern in monkeyflowers (Mimulus).

The origin of phenotypic novelty is one of the most challenging problems in evolutionary biology. Although genetic regulatory network rewiring or co-option has been widely recognised as a major contributor, in most cases how such genetic rewiring/co-option happens is completely unknown. We have studied a novel foliar pigmentation pattern that evolved recently in the monkeyflower species Mimulus verbenaceus. Through genome-wide association tests using wild-collected samples, experimental crosses of laboratory inbred lines, gene expression analyses, and functional assays, we identified an anthocyanin-activating R2R3-MYB gene, STRIPY, as the causal gene triggering the emergence of the discrete, mediolateral anthocyanin stripe in the M. verbenaceus leaf. Chemical mutagenesis revealed the existence of upstream activators and repressors that form a 'hidden' prepattern along the leaf proximodistal axis, potentiating the unique expression pattern of STRIPY. Population genomics analyses did not reveal signatures of positive selection, indicating that nonadaptive processes may be responsible for the establishment of this novel trait in the wild. This study demonstrates that the origin of phenotypic novelty requires at least two separate phases, potentiation and actualisation. The foliar stripe pattern of M. verbenaceus provides an excellent platform to probe the molecular details of both processes in future studies.

Association mapping across a multitude of traits collected in diverse environments in maize.

Classical genetic studies have identified many cases of pleiotropy where mutations in individual genes alter many different phenotypes. Quantitative genetic studies of natural genetic variants frequently examine one or a few traits, limiting their potential to identify pleiotropic effects of natural genetic variants. Widely adopted community association panels have been employed by plant genetics communities to study the genetic basis of naturally occurring phenotypic variation in a wide range of traits. High-density genetic marker data—18M markers—from 2 partially overlapping maize association panels comprising 1,014 unique genotypes grown in field trials across at least 7 US states and scored for 162 distinct trait data sets enabled the identification of of 2,154 suggestive marker-trait associations and 697 confident associations in the maize genome using a resampling-based genome-wide association strategy. The precision of individual marker-trait associations was estimated to be 3 genes based on a reference set of genes with known phenotypes. Examples were observed of both genetic loci associated with variation in diverse traits (e.g., above-ground and below-ground traits), as well as individual loci associated with the same or similar traits across diverse environments. Many significant signals are located near genes whose functions were previously entirely unknown or estimated purely via functional data on homologs. This study demonstrates the potential of mining community association panel data using new higher-density genetic marker sets combined with resampling-based genome-wide association tests to develop testable hypotheses about gene functions, identify potential pleiotropic effects of natural genetic variants, and study genotype-by-environment interaction.

Abstract 752: Unveiling Korean cancer-associated gene using large-size cancer germline mutation data

Abstract We are focusing on the germline mutation data to understand the possible cancer-causing gene mutation that has a chance of inheritability to the next generation. Cancer genomics has been already widely studied around the world in a pan-cancer manner. But we found that the majority of the ethnicity of the data sequenced is mainly the US and European origin. For the Korean cancer cohort, it is clear that the lack of sample size was the bottleneck for ethnicity-specific studies. It is necessary that there is a limited number of the study contribute to the knowledge that Korean specifically applicated to explore the possible association between germline mutation and cancer occurrences. The objective of this study is to discover the Korean-specific candidate genes that associate with the tumor.Our study collected around 3000 Korean-specific samples consisting of various cancer types and normal control. We also gathered normal control samples for 354 Super-Normal (tumor-free, age &amp;lt; 65, med-checked) samples, and 1094 Korean normal (U1K) samples. Whole Exome Sequencing has been applied for every sample except U1K cohort that has already been whole genome sequenced. Genome-Wide Association Test (GWAS) has been executed between Korean-specific cancer patients and Korean normal samples. The study has been dichotomously analyzed, common variants are studied by GWAS fashion, and the rare variants are studied by gene-level aggregated fashion. Not only statistically, but also functionally we make use of the knowledge that Nonsense Mediated Decay (NMD) information to break the limitation of the unexplained gene mutation that does not follow the Central Dogma. Clinical validation data is also utilized. In a clinical aspect, we validated the dataset with a Clinvar and decided whether the mutation has a piece of clinical evidence or not.By conducting a series of studies, we have successfully found that some candidate genes which are known for DNA binding genes including PABPC1, PABPC3, and ZNF717 were significantly associated. Indeed, a cell division cycle associated gene like CDC27 also represents a significant association with cancer phenotype. Furthermore, ATXN3, SEPT2, PCMTD1 mutation is observed more in the cancer cohort. We are performing comparison studies to further elucidate which ethnic group represents more gene mutation on different cancer types.In summary, we propose the method that presents the possible germline mutation that is associated with phenotype by various factors, and also proposed Korean-specific candidate genes that associate with cancer. Citation Format: Gangpyo Yuh, Seulki Song, Eunju Cho, Miso Kim, Hyery Kim, Youngil Koh, Jookyung Park, Sungsoo Yoon, Sehoon Lee. Unveiling Korean cancer-associated gene using large-size cancer germline mutation data [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 752.

Genetics of Base Coat Colour Variations and Coat Colour-Patterns of the South African Nguni Cattle Investigated Using High-Density SNP Genotypes.

Nguni cattle are a Sanga type breed with mixed B. taurus and B. indicus ancestry and proven resistance to ticks, diseases and other harsh conditions of the African geographical landscape. The multi-coloured Nguni coats have found a niche market in the leather industry leading to breeding objectives towards the promotion of such diversity. However, there is limited studies on the genomic architecture underlying the coat colour and patterns hampering any potential breeding and improvement of such trait. This study investigated the genetics of base coat colour, colour-sidedness and the white forehead stripe in Nguni cattle using coat colour phenotyped Nguni cattle and Illumina Bovine HD (770K) genotypes. Base coat colour phenotypes were categorised into eumelanin (n = 45) and pheomelanin (n = 19). Animals were categorised into either colour-sided (n = 46) or non-colour-sided (n = 94) and similarly into presence (n = 15) or absence (n = 67) of white forehead stripe. Genome-wide association tests were conducted using 622,103 quality controlled SNPs and the Efficient Mixed Model Association eXpedited method (EMMAX) implemented in Golden Helix SNP Variation Suite. The genome-wide association studies for base coat colour (eumelanin vs. pheomelanin) resulted into four indicative SNPs on BTA18 and a well-known gene, MC1R, was observed within 1 MB from the indicative SNPs (p < 0.00001) and found to play a role in the melanogenesis (core pathway for melanin production) and the MAPK signalling pathway. GWAS for colour-sidedness resulted in four indicative SNPs, none of which were in close proximity to the KIT candidate gene known for colour-sidedness. GWAS for the white forehead stripe resulted in 17 indicative SNPs on BTA6. Four genes MAPK10, EFNA5, PPP2R3C and PAK1 were found to be associated with the white forehead stripe and were part of the MAPK, adrenergic and Wnt signalling pathways that are synergistically associated with the synthesis of melanin. Overall, our results prove prior knowledge of the role of MC1R in base coat colours in cattle and suggested a different genetic mechanism for forehead stripe phenotypes in Nguni cattle.

MP05-06 GENETIC ANALYSIS OF KIDNEY STONE DISEASE IN A MULTI-ETHNIC COHORT: INSIGHTS FROM GENOME-WIDE AND PHENOME-WIDE ASSOCIATION STUDIES

You have accessJournal of UrologyCME1 May 2022MP05-06 GENETIC ANALYSIS OF KIDNEY STONE DISEASE IN A MULTI-ETHNIC COHORT: INSIGHTS FROM GENOME-WIDE AND PHENOME-WIDE ASSOCIATION STUDIES Parth Patel, Vidhya Venkateswaran, Bogdan Pasanuic, and Kymora Scotland Parth PatelParth Patel More articles by this author , Vidhya VenkateswaranVidhya Venkateswaran More articles by this author , Bogdan PasanuicBogdan Pasanuic More articles by this author , and Kymora ScotlandKymora Scotland More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002522.06AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Nephrolithiasis, a common global ailment with significant clinical and economic health burden, has demonstrated heritability up to 56%. Various single nucleotide polymorphisms (SNPs) have been implicated in the development of kidney stone disease. Existing literature regarding this association is primarily in the form of genome-wide association studies or based on geographically limited samples. This genome- and phenome-wide association study aimed to evaluate the link between SNPs and kidney stone disease in a database of patients representing diverse ancestral backgrounds. METHODS: We retrospectively studied our repository of more than 27000 genotyped patients and their de-identified electronic health records. ICD-10 codes were aggregated to provide clinically meaningful groupings called phecodes. Genome-wide association testing was performed between all genotyped SNPs and phecodes associated with urolithiasis. We also tested the association between selected SNPs from our genome-wide association analysis and 1330 phecodes in the biobank to ascertain other phenotypic associations. RESULTS: The ancestry breakdown of these patients was 72.8% European, 16.3% Admixed American, 7.41% Eastern Asian, and 3.45% African. The lead SNPs from the trans-ancestry meta-analysis were rs2263090 and rs79616469 with p-values approaching genome-wide significance threshold of 5e-08 (Figure 1). In the phenome-wide association analysis, SNP rs2263090 showed associations with other kidney-related traits such as hematuria in EUR (Figure 2). CONCLUSIONS: While numerous polymorphisms have been associated with kidney stone disease, our genome-wide and phenome-wide association studies suggest that their phenotypic expression may not be equal across genetic ancestral groupings. This promotes the concept that inheritable causes of nephrolithiasis are likely polygenic and their expression multifactorial, and much still remains to be learned about the molecular basis of kidney stone formation. Source of Funding: N/A © 2022 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 207Issue Supplement 5May 2022Page: e69 Advertisement Copyright & Permissions© 2022 by American Urological Association Education and Research, Inc.MetricsAuthor Information Parth Patel More articles by this author Vidhya Venkateswaran More articles by this author Bogdan Pasanuic More articles by this author Kymora Scotland More articles by this author Expand All Advertisement PDF DownloadLoading ...

Genomic insights into the genetic signatures of selection and seed trait loci in cultivated peanut

IntroductionCultivated peanut (Arachis hypogaea L.) is an important oil crop for human nutrition and is cultivated in >100 countries. However, the present knowledge of its genomic diversity, evolution, and loci related to the seed traits is limited. ObjectivesOur study intended to (1) uncover the population structure and the demographic history of peanuts, (2) identify signatures of selection that occurred during peanut improvement breeding, and (3) detect and verify the functions of candidate genes associated with seed traits. MethodsWe explored the population relationship and the evolution of peanuts using a largescale single nucleotide polymorphism dataset generated from the genome-wide resequencing of 203 cultivated peanuts. Genetic diversity and genomic scan analyses were applied to identify selective loci for genomic-selection breeding. Genome-wide association studies, transgenic experiments, and RNA-seq were employed to identify the candidate genes associated with seed traits. ResultsOur study revealed that the 203 resequenced accessions were divided into four genetic groups, consistent with their botanical classification. Moreover, the var. peruviana and var. fastigiata subpopulations have diverged to a greater extent than the others, and var. peruviana may be the earliest variant in the evolution from tetraploid ancestors. A recent dramatic expansion in the effective population size of the cultivated peanuts ca. 300–500 years ago was also noted. Selective sweeps underlying quantitative trait loci and genes of seed size, plant architecture, and disease resistance coincide with the major goals of improved peanut breeding compared with the landrace and cultivar populations. Genome-wide association testing with functional analysis led to the identification of two genes involved in seed weight and seed length regulation. ConclusionOur study provides valuable information for understanding the genomic diversity and the evolution of peanuts and serves as a genomic basis for improving peanut cultivars.

Young Pakistani Individuals are Genetically Predisposed to Lumbar Degenerative Disc Degeneration

Aim: Even though the specific processes that cause degenerative disc degeneration are unknown, a major hereditary effect has indeed been discovered. Concentrating on DDD in emerging adults can help determine the precise role of genetic susceptibility to DDD. Methods: MRI imaging (1.6 Tesla) was used to analyses individuals (41 years old) having lumbar disc degeneration, and genome wide association testing was made for 58 single nucleotide polymorphisms in 38 potential genes. Pfirrman's grading had been used to classify disc degeneration in specific lumbar spine discs from L1 to S1. The participants have been divided into 2 sets based on their Total Disc Degenerative Score. DDD intensity has been rated as mild or severe depending on TDDS. Results: MRI imaging (1.6 Tesla) was used to analyze individuals (41 years old) having lumbar disc degeneration, and genome wide association testing was made for 58 single nucleotide polymorphisms in 38 potential genes. Pfirrman's grading had been used to classify disc degradation in specific lumbar spine discs from L1 to S1. The participants have been divided into 2 sets grounded on their Total Disc Degenerative Score. DDD intensity has been rated as moderately severe depending on TDDS. Conclusion: The researchers discovered significant SNP correlations of five genes in young people with serious lumbar disc degeneration. Those five genes have various roles in matrix metabolism, intracellular transmission, and the inflammatory cascade. The current demonstrates that disc degeneration is very complicated illness characterized by the intricate interaction of several genetic variations. Keywords: Lumbar Degenerative Disc, Degeneration, Predisposed.

Genome-Wide Association Study of Ustekinumab Response in Psoriasis.

Heterogeneous genetic and environmental factors contribute to the psoriasis phenotype, resulting in a wide range of patient response to targeted therapies. Here, we investigate genetic factors associated with response to the IL-12/23 inhibitor ustekinumab in psoriasis. To date, only HLA-C*06:02 has been consistently reported to associate with ustekinumab response in psoriasis. Genome-wide association testing was performed on the continuous outcome of percent change in Psoriasis Area Severity Index (PASI) at 12 weeks of ustekinumab therapy relative to baseline. A total of 439 European ancestry individuals with psoriasis were included [mean age, 46.6 years; 277 men (63.1%)]. 310 (70.6%) of the participants comprised the discovery cohort and the remaining 129 (29.4%) individuals comprised the validation cohort. Chromosome 4 variant rs35569429 was significantly associated with ustekinumab response at 12 weeks at a genome-wide significant level in the discovery cohort and replicated in the validation cohort. Of psoriasis subjects with at least one copy of the deletion allele of rs35569429, 44% achieved PASI75 (75% improvement in PASI from baseline) at week 12 of ustekinumab treatment, while for subjects without the deletion allele, 75% achieved PASI75 at week 12. We found that differences in treatment response increased when rs35569429 was considered alongside HLA-C*06:02. Psoriasis patients with the deletion allele of rs35569429 who were HLA-C*06:02 negative had a PASI75 response rate of 35% at week 12, while those without the deletion allele who were HLA-C*06:02 positive had a PASI75 response rate of 82% at week 12. Through GWAS, we identified a novel SNP that is potentially associated with response to ustekinumab in psoriasis.

DOP09 Phenotypic and genetic determinants of medication response in patients in the UK IBD BioResource

Abstract Background Inflammatory bowel disease (IBD) exhibits heterogeneity at genetic, phenotypic, and therapeutic levels [1]. Although several studies have investigated genetic effects on IBD subtypes and drug adverse events [2,3], few have comprehensively explored the phenotypic and genetic determinants of IBD drug efficacy in a sufficiently powered cohort. Methods We used data from 32,199 patients in the UK IBD BioResource to investigate the effects of clinical phenotypes and demographics on drug efficacy and combined this with genome-wide genetic data for a subset of 11,536 individuals (Table 1). Drug efficacy was defined using a combination of clinician reported efficacy and persistence on drug without treatment escalation. Anti-TNF, thiopurine, steroids, and mesalazine were explored. We estimated phenotypic effects on drug efficacy using multivariable logistic regression and the genetic effects by genome-wide logistic regression. To explore whether drug efficacy and IBD disease susceptibility share a genetic basis, we estimated the proportion of variance in drug efficacy explained by known IBD risk variants [4]. Associations with Bonferroni corrected P-values &amp;lt; 0.05 were defined as statistically significant in phenotypic analyses and a genome-wide significance threshold of P=5x10-8 was adopted for genetic analyses. Results Drug efficacy was generally lower in patients with Crohn’s disease (CD) compared to those with other subtypes (OR ranges from 0.40 to 0.79), but anti-TNF showed a higher efficacy rate (OR = 1.21) in CD patients. Increasing age at diagnosis was associated with evidence of increased efficacy of thiopurine and mesalazine (Table 2). We found evidence of a genetic contribution to variation in drug efficacy for most drugs studied. However, known IBD risk variants showed little contribution (Figure 1). Using genome-wide association testing, we identified three loci showing a significant association with drug efficacy; two were related to steroid response and one to thiopurines (Table 3). None of these was an IBD disease susceptibility locus (P &amp;gt; 0.05). Conclusion Using a large, well-characterised cohort we found both genetic and phenotypic determinants of drug efficacy. Three loci were reported to be associated with drug efficacy in the first phase of the genetic analysis; at least 4,200 extra genotyped samples will be included before the ECCO meeting, thus increasing the power to detect additional loci. Our results suggest the genetic causes of drug efficacy and disease susceptibility are largely independent. These findings may provide opportunities for exploring the biology of drug efficacy and improving medication prioritization in IBD patients.

Adaptive divergence in bill morphology and other thermoregulatory traits is facilitated by restricted gene flow in song sparrows on the California Channel Islands.

Disentangling the effects of neutral and adaptive processes in maintaining phenotypic variation across environmental gradients is challenging in natural populations. Song sparrows (Melospiza melodia) on the California Channel Islands occupy a pronounced east-west climate gradient within a small spatial scale, providing a unique opportunity to examine the interaction of genetic isolation (reduced gene flow) and the environment (selection) in driving variation. We used reduced representation genomic libraries to infer the role of neutral processes (drift and restricted gene flow) and divergent selection in driving variation in thermoregulatory traits with an emphasis on the mechanisms that maintain bill divergence among islands. Analyses of 22,029 neutral SNPs confirm distinct population structure by island with restricted gene flow and relatively large effective population sizes, suggesting bill differences are probably not a product of genetic drift. Instead, we found strong support for local adaptation using 3294 SNPs in differentiation-based and environmental association analyses coupled with genome-wide association tests. Specifically, we identified several putatively adaptive and candidate loci in or near genes involved in bill development pathways (e.g., BMP, CaM, Wnt), confirming the highly complex and polygenic architecture underlying bill morphology. Furthermore, we found divergence in genes associated with other thermoregulatory traits (i.e., feather structure, plumage colour, and physiology). Collectively, these results suggest strong divergent selection across an island archipelago results in genomic changes in a suite of traits associated with climate adaptation over small spatial scales. Future research should move beyond studying univariate traits to better understand multidimensional responses to complex environmental conditions.