Non-synonymous Variants Research Articles

Analysis of randomly mutated AlSRKb genes reveals that most loss-of-function mutations cause defects in plasma membrane localization.

Only very limited information is available on why some nonsynonymous variants severely alter gene function while others have no effect. To identify the characteristic features of mutations that strongly influence gene function, this study focused on SRK which encodes a highly polymorphic receptor kinase expressed in stigma papillary cells that underlies a female determinant of self-incompatibility in Brassicaceae. A set of 300 Arabidopsis thaliana transformants expressing mutated SRKb from A. lyrata was constructed using error-prone PCR and the genotype and self-incompatibility phenotype of each transformant were determined. Almost all the transformants showing the self-incompatibility defect contained mutations in AlSRKb that altered localization to the plasma membrane. The observed mutations occurred in amino acid residues that were highly conserved across S haplotypes and whose predicted locations were in the interior of the protein. Our findings suggested that mutations causing the self-incompatibility defect were more likely to result from changes to AlSRKb biosynthesis than from loss of AlSRKb function. In addition, we examined whether the RandomForest and Extreme Gradient Boosting methods could predict the self-incompatibility phenotypes of SRK mutants.

Genome-wide association study and molecular marker development for susceptibility to Gibberella ear rot in maize.

Sixty-nine quantitative trait nucleotides conferring maize resistance to Gibberella ear rot were detected, including eighteen novel loci. Four candidate genes were predicted, and four kompetitive allele-specific PCR markers were developed. Maize Gibberella ear rot (GER), caused by Fusarium graminearum, is one of the most devastating diseases in maize-growing regions worldwide. Enhancing maize cultivar resistance to this disease requires a comprehensive understanding of the genetic basis of resistance to GER. In this study, 334 maize inbred lines were phenotyped for GER resistance in five environments and genotyped using the Affymetrix CGMB56K SNP Array, and a genome-wide association study of resistance to GER was performed using a 3V multi-locus random-SNP-effect mixed linear model. A total of 69 quantitative trait nucleotides (QTNs) conferring resistance to GER were detected, and all of them explained individually less than 10% of the phenotypic variation, suggesting that resistance to GER is controlled by multiple minor-effect genetic loci. A total of 348 genes located around the 200-kb genomic region of these 69 QTNs were identified, and four of them (Zm00001d029648, Zm00001d031449, Zm00001d006397, and Zm00001d053145) were considered candidate genes conferring susceptibility to GER based on gene expression patterns. Moreover, four kompetitive allele-specific PCR markers were developed based on the non-synonymous variation of these four candidate genes and validated in two genetic populations. This study provides useful genetic resources for improving resistance to GER in maize.

STUDY OF SOMATIC AND GERMINAL MUTATIONS IN ARTERIOVENOUS MALFORMATIONS OF THE BRAIN USING WHOLE EXOME SEQUENCING

Rare vascular lesions known as brain arteriovenous malformations (bAVMs) are caused by shunts between cerebral arteries and veins that do not involve the capillary bed. The majority of bAVMs do not cause any symptoms, however some can be controlled by seizures and result in potentially fatal brain hemorrhages. Over the past ten years, significant advancements in our understanding of bAVM pathogenesis have been accomplished, primarily through the use of genome sequencing and biomolecular analysis. An autosomal dominant vascular disorder called Hereditary Hemorrhagic Telangiectasia (HHT, also known as Rendu-Osler-Weber Syndrome) affects about 1 in 5000 people globally and is associated with about 5% of brain AVMs, while the remaining 95% are due to sporadic mutations. The major aim of the project is to investigate genetic causes of sporadic forms of AVMs in the brain by means of whole-exome sequencing of tissues with AVM lesions and blood samples. Analysis of somatic mutations will broaden the understanding of AVM pathogenesis. This study was carried out in accordance with the Declaration of Helsinki's tenets and approved by the National Center of Biotechnology 's ethics committee (№9, 7 November 2023, ) Astana). Based on clinical data, the age range of the patients at the onset of the disease also encompassed 25 to 40 years. To confirm the diagnosis, MRI and CAG data were used to validate the diagnosis. Each patient completed a specially designed questionnaire with medical information (such as age of debut and type of course) and demographic data (such as age, gender, and nationality). Three patients were classified as having a Spetzler-Martin grade II, while one patient was categorized as grade III. The sizes of arteriovenous malformations (AVMs) varied from 0 to 3 mm in one patient (grade II) to 3 to 6 mm in three patients (grades II-III). AVM tissue specimens were obtained during clinically necessary procedures. Brain AVM tissues were collected during surgery, which involved trepanation and excision of the AVM. Blood samples were also collected from these patients. Both DNA and RNA were isolated from these tissue and blood samples for subsequent exome sequencing an. Qubit 2.0 fluorometer was employed for more precise determination of DNA concentration, given that the nucleic acids will be utilized in future whole exome sequencing analysis. Whole exome sequencing was performed on six samples (blood and tissue) by Novaseq 6000 (Illumina). The annotated results were analyzed for the presence of single-nucleotide polymorphisms (SNP) and insertion-deletion mutations (Indels) between DNAs from the AVM tissue sample and blood. The GATK workflow was used for the analysis and annotation of the raw data, and vcf files were generated. Then, the variants were filtered for a quality ≥ 30 in Excel 1st blood 117554, 1st tissue 114715; 2nd blood 112972, 2nd tissue 116022; 3rd blood 112859, 3rd tissue 117168 and genotype differences between tissue and blood DNA samples 1st blood 114512, 1st tissue 111682; 2nd blood 110614, 2nd tissue 111982; 3rd blood 110564, 3rd tissue 112805. After selecting only non-synonymous, frameshift insertions and deletions variants with different genotypes in the blood and tissue samples, 1st blood 279, 1st tissue 277; 2nd blood 279, 2nd tissue 271; 3rd blood 275, 3rd tissue 268 variations were observed. Analysis of whole-exome data continues.

Investigating the prevalence of MFN2 mutations in amyotrophic lateral sclerosis: insights from an Italian cohort.

The MFN2 gene encodes mitofusin 2, a key protein for mitochondrial fusion, transport, maintenance and cell communication. MFN2 mutations are primarily linked to Charcot-Marie-Tooth disease type 2A. However, a few cases of amyotrophic lateral sclerosis and amyotrophic lateral sclerosis/frontotemporal dementia phenotypes with concomitant MFN2 mutations have been previously reported. This study examines the clinical and genetic characteristics of an Italian cohort of amyotrophic lateral sclerosis patients with rare, non-synonymous MFN2 mutations. A group of patients (n = 385) diagnosed with amyotrophic lateral sclerosis at our Neurology Units between 2008 and 2023 underwent comprehensive molecular testing, including MFN2. After excluding pathogenic mutations in the main amyotrophic lateral sclerosis-related genes (i.e. C9orf72, SOD1, FUS and TARDBP), MFN2 variants were classified based on the American College of Medical Genetics and Genomics guidelines, and demographic and clinical data of MFN2-mutated patients were retrieved. We identified 12 rare, heterozygous, non-synonymous MFN2 variants in 19 individuals (4.9%). Eight of these variants, carried by nine patients (2.3%), were either pathogenic, likely pathogenic or variants of unknown significance according to the American College of Medical Genetics and Genomics guidelines. Among these patients, four exhibited a familial pattern of inheritance. The observed phenotypes included classic and bulbar amyotrophic lateral sclerosis, amyotrophic lateral sclerosis/frontotemporal dementia, flail arm, flail leg and progressive muscular atrophy. Median survival after disease onset was extremely variable, ranging from less than 1 to 13 years. This study investigates the prevalence of rare, non-synonymous MFN2 variants within an Italian cohort of amyotrophic lateral sclerosis patients, who have been extensively investigated, enhancing our knowledge of the underlying phenotypic spectrum. Further research is needed to understand whether MFN2 mutations contribute to motor neuron disease and to what extent. Improving our knowledge regarding the genetic basis of amyotrophic lateral sclerosis is crucial both in a diagnostic and therapeutic perspective.

Identification and functional validation of rare coding variants in genes linked to monogenic obesity.

Rare cases of monogenic obesity, which may respond to specific therapeutics, can remain undetected in populations in whichpolygenic obesity is prevalent. This study examined rare DNA variation in established monogenic obesity genes within a community using whole-exome sequence data from 6803 longitudinally studied individuals. Exome data across 15 monogenic obesity genes were analyzed for nonsynonymous variants observed in any child with a maximum BMI z score > 2 (N = 279) but not observed in a child with a maximum BMI z score ≤ 0 (n = 1542) or that occurred in adults in the top 5th percentile of BMI (n = 263) but not in adults below the median BMI (n = 2629). Variants were then functionally analyzed using luciferase assays. The comparisons between cases of obesity and controls identified eight missense variants in six genes: DYRK1B, KSR2, MC4R, NTRK2, PCSK1, and SIM1. Among these, MC4R p.A303P and p.R165G were previously shown to impair MC4R function. Functional analyses of the remaining six variants suggest that KSR2 p.I402F and p.T193I and NTRK2 p.S249Y alter protein function. In addition to MC4R, rare missense variants in KSR2 and NTRK2 may potentially explain the severe obesity observed for the carriers.

Variant Impact Predictor database (VIPdb), version 2: trends from three decades of genetic variant impact predictors

BackgroundVariant interpretation is essential for identifying patients’ disease-causing genetic variants amongst the millions detected in their genomes. Hundreds of Variant Impact Predictors (VIPs), also known as Variant Effect Predictors (VEPs), have been developed for this purpose, with a variety of methodologies and goals. To facilitate the exploration of available VIP options, we have created the Variant Impact Predictor database (VIPdb).ResultsThe Variant Impact Predictor database (VIPdb) version 2 presents a collection of VIPs developed over the past three decades, summarizing their characteristics, ClinGen calibrated scores, CAGI assessment results, publication details, access information, and citation patterns. We previously summarized 217 VIPs and their features in VIPdb in 2019. Building upon this foundation, we identified and categorized an additional 190 VIPs, resulting in a total of 407 VIPs in VIPdb version 2. The majority of the VIPs have the capacity to predict the impacts of single nucleotide variants and nonsynonymous variants. More VIPs tailored to predict the impacts of insertions and deletions have been developed since the 2010s. In contrast, relatively few VIPs are dedicated to the prediction of splicing, structural, synonymous, and regulatory variants. The increasing rate of citations to VIPs reflects the ongoing growth in their use, and the evolving trends in citations reveal development in the field and individual methods.ConclusionsVIPdb version 2 summarizes 407 VIPs and their features, potentially facilitating VIP exploration for various variant interpretation applications. VIPdb is available at https://genomeinterpretation.org/vipdb

Host specificity and cophylogeny in the “animal-gut bacteria-phage” tripartite system

Cophylogeny has been identified between gut bacteria and their animal host and is highly relevant to host health, but little research has extended to gut bacteriophages. Here we use bee model to investigate host specificity and cophylogeny in the “animal-gut bacteria-phage” tripartite system. Through metagenomic sequencing upon different bee species, the gut phageome revealed a more variable composition than the gut bacteriome. Nevertheless, the bacteriome and the phageome showed a significant association of their dissimilarity matrices, indicating a reciprocal interaction between the two kinds of communities. Most of the gut phages were host generalist at the viral cluster level but host specialist at the viral OTU level. While the dominant gut bacteria Gilliamella and Snodgrassella exhibited matched phylogeny with bee hosts, most of their phages showed a diminished level of cophylogeny. The evolutionary rates of the bee, the gut bacteria and the gut phages showed a remarkably increasing trend, including synonymous and non-synonymous substitution and gene content variation. For all of the three codiversified tripartite members, however, their genes under positive selection and genes involving gain/loss during evolution simultaneously enriched the functions into metabolism of nutrients, therefore highlighting the tripartite coevolution that results in an enhanced ecological fitness for the whole holobiont.

Germline variant profiling of CHEK2 sequencing variants in breast cancer patients

The cell cycle checkpoint kinase 2 (CHEK2) is a tumor suppressor gene coding for a protein kinase with a role in the cell cycle and DNA repair pathways. Variants within CHEK2 are associated with an increased risk of developing breast, colorectal, prostate and several other types of cancer. Comprehensive genetic risk assessment leads to early detection of hereditary cancer and provides an opportunity for better survival. Multigene panel screening can identify the presence of pathogenic variants in hereditary cancer predisposition genes (HCPG), including CHEK2. Multigene panels, however, also result in large quantities of genetic data some of which cannot be interpreted and are classified as variants of uncertain significance (VUS). A VUS provides no information for use in medical management and leads to ambiguity in genetic counseling. In the absence of variant segregation data, in vitro functional analyses can be used to clarify variant annotations, aiding in accurate clinical management of patient risk and treatment plans. In this study, we performed whole exome sequencing (WES) to investigate the prevalence of germline variants in 210 breast cancer (BC) patients and conspicuously among the many variants in HCPGs that we found, we identified 16 individuals with non-synonymous or frameshift CHEK2 variants, sometimes along with additional variants within other BC susceptibility genes. Using this data, we investigated the prevalence of these CHEK2 variants in African American (AA) and Caucasian (CA) populations identifying the presence of two novel frameshift variants, c.1350delA (p.Val451Serfs*18) and c.1528delC (p.Gln510Argfs*3) and a novel missense variant, c262C>T (p.Pro88Ser). Along with the current clinical classifications, we assembled available experimental data and computational predictions of function for these CHEK2 variants, as well as explored the role these variants may play in polygenic risk assessment.

An extensive in silico analysis of missense mutations of the human AIMP2 gene

HLD17 (Hypomyelinating Leukodystrophy 17) is an inherited white matter disorder characterized by insufficient myelin production due to biallelic loss of function mutations in the aminoacyl-tRNA synthetase complex-interacting multifunctional protein 2 (AIMP2) gene. In silico analysis of SNVs (single nucleotide variants) in the AIMP2 gene is an efficient and cost-effective method for analyzing and predicting the impact of mutations on protein function and disease pathophysiology.The study used dbSNP and Ensembl databases to obtain data on 343 nonsynonymous single nucleotide variants (nsSNVs) in the human AIMP2 gene. Six prediction algorithm tools were used to assess the effects of these nsSNVs on AIMP2's functions and structures. Results showed that 18 nsSNVs were located within functional domains, while 10 nsSNVs led to decreased protein stability. The structural and functional properties of the AIMP2 protein were investigated using databases such as Predict Protein, Mutpred2, and HOPE. ConSurf analysis provided information about conserved nsSNVs. GeneMANIA and STRING software tools were used to predict interactions between gene-gene and protein-protein, respectively. Phyre2 and I-TASSER web servers were used to predict the 3D structures of wild-type and mutant proteins.In addition, having the challenge of probable post-translational modification sites in the AIMP2, we made predictions using various bioinformatics tools. Consecuently, three minor mutations (L138Q, V161E, and I188N) and five major mutations (C23S, D121G, I122S, P128S, and W268S) were found to affect the AIMP2 protein's structure or function. Anyway, These mutations need to be further studied and confirmed through experimental investigation and GWAS studies.

Comprehensive analysis of the functional impact of single nucleotide variants of human CHEK2.

Loss of function mutations in the checkpoint kinase gene CHEK2 are associated with increased risk of breast and other cancers. Most of the 3,188 unique amino acid changes that can result from non-synonymous single nucleotide variants (SNVs) of CHEK2, however, have not been tested for their impact on the function of the CHEK2-enocded protein (CHK2). One successful approach to testing the function of variants has been to test for their ability to complement mutations in the yeast ortholog of CHEK2, RAD53. This approach has been used to provide functional information on over 100 CHEK2 SNVs and the results align with functional assays in human cells and known pathogenicity. Here we tested all but two of the 4,887 possible SNVs in the CHEK2 open reading frame for their ability to complement RAD53 mutants using a high throughput technique of deep mutational scanning (DMS). Among the non-synonymous changes, 770 were damaging to protein function while 2,417 were tolerated. The results correlate well with previous structure and function data and provide a first or additional functional assay for all the variants of uncertain significance identified in clinical databases. Combined, this approach can be used to help predict the pathogenicity of CHEK2 variants of uncertain significance that are found in susceptibility screening and could be applied to other cancer risk genes.

Discovering novel germline genetic variants linked to severe fluoropyrimidine-related toxicity in- and outside DPYD

BackgroundThe Alpe-DPD study (NCT02324452) demonstrated that prospective genotyping and dose-individualization using four alleles in DPYD (DPYD*2A/rs3918290, c.1236G > A/rs75017182, c.2846A > T/rs67376798 and c.1679 T > G/rs56038477) can mitigate the risk of severe fluoropyrimidine toxicity. However, this could not prevent all toxicities. The goal of this study was to identify additional genetic variants, both inside and outside DPYD, that may contribute to fluoropyrimidine toxicity.MethodsBiospecimens and data from the Alpe-DPD study were used. Exon sequencing was performed to identify risk variants inside DPYD. In silico and in vitro analyses were used to classify DPYD variants. A genome-wide association study (GWAS) with severe fluoropyrimidine-related toxicity was performed to identify variants outside DPYD. Association with severe toxicity was assessed using matched-pair analyses for the exon sequencing and logistic, Cox, and ordinal regression analyses for GWAS.ResultsTwenty-four non-synonymous, frameshift, and splice site DPYD variants were detected in ten of 986 patients. Seven of these variants (c.1670C > T, c.1913 T > C, c.1925 T > C, c.506delC, c.731A > C, c.1740 + 1G > T, c.763 − 2A > G) were predicted to be deleterious. The carriers of either of these variants showed a trend towards a 2.14-fold (95% CI, 0.41–11.3, P = 0.388) increased risk of severe toxicity compared to matched controls (N = 30). After GWAS of 942 patients, no individual single nucleotide polymorphisms achieved genome-wide significance (P ≤ 5 × 10−8), however, five variants were suggestive of association (P < 5 × 10−6) with severe toxicity.ConclusionsResults from DPYD exon sequencing and GWAS analysis did not identify additional genetic variants associated with severe toxicity, which suggests that testing for single markers at a population level currently has limited clinical value. Identifying additional variants on an individual level is still promising to explain fluoropyrimidine-related severe toxicity. In addition, studies with larger samples sizes, in more diverse cohorts are needed to identify potential clinically relevant genetic variants related to severe fluoropyrimidine toxicity.

Discovery and computational exploration of SNPs in GNRHR gene and their influence on protein structure and function in Indian goat breeds

This study focuses on identifying functional single nucleotide polymorphisms (SNPs) within the gonadotropin-releasing hormone receptor (GNRHR) gene and conducting subsequent in-silico analysis of their effects on protein structure and function in two distinct South Indian goat breeds, namely Attapady Black (n = 120) and Malabari goats (n = 180), known for their divergent prolificacy traits. Utilizing a DNA pool sequencing assay, ten SNPs were uncovered in the study population: c.-1129T>G, c.-1069A>G, c.-978A>C, c.-605A>G, c.-33A>G, c.-29T>G, c.48G>A, c.75G>A, c.209T>G, and c.*212A>G. Notably, two polymorphisms, c.-1129T>G and c.-33A>G, were novel. Additionally, two polymorphisms, c.-33A>G and c.-978A>C, were exclusive to Malabari goats. Analysis of upstream variants revealed modifications to transcription factor and micro-RNA (miRNA) binding sites, suggesting potential alterations in GNRHR expression. Of particular significance was the non-synonymous exonic variant at c.209T>G locus, resulting in methionine to arginine substitution at the 70th position within the first intracellular loop of the receptor protein. This amino acid change may have implications for the functional dynamics of the receptor as GnRHR intracellular loops are involved in G protein coupling thereby facilitation of downstream signalling pathways. The identified SNPs and their in-silico impact analysis contribute to our understanding of the molecular mechanisms underlying reproductive traits in these goat populations, with implications for future breeding strategies and genomic selection programs.

SEC16A Variants Predispose to Chronic Pancreatitis by Impairing ER-to-Golgi Transport and Inducing ER Stress.

Chronic pancreatitis (CP) is a complex disease with genetic and environmental factors at play. Through trio exome sequencing, a de novo SEC16A frameshift variant in a Chinese teenage CP patient is identified. Subsequent targeted next-generation sequencing of the SEC16A gene in 1,061 Chinese CP patients and 1,196 controls reveals a higher allele frequency of rare nonsynonymous SEC16A variants in patients (4.90%vs 2.93%; odds ratio [OR], 1.71; 95% confidence interval [CI], 1.26-2.33). Similar enrichments are noted in a French cohort (OR, 2.74; 95% CI, 1.67-4.50) and in a biobank meta-analysis (OR, 1.16; 95% CI, 1.04-1.31). Notably, Chinese CP patients with SEC16A variants exhibit a median onset age 5 years earlier than those without (40.0vs 45.0; p=0.012). Functional studies using three CRISPR/Cas9-edited HEK293T cell lines show that loss-of-function SEC16A variants disrupt coat protein complex II (COPII) formation, impede secretory protein vesicles trafficking, and induce endoplasmic reticulum (ER) stress due to protein overload. Sec16a+/- mice, which demonstrate impaired zymogen secretion and exacerbated ER stress compared to Sec16a+/+, are further generated. In cerulein-stimulated pancreatitis models, Sec16a+/- mice display heightened pancreatic inflammation and fibrosis compared to wild-type mice. These findings implicate a novel pathogenic mechanism predisposing to CP.

Genetic evidence for predisposition to acute leukemias due to a missense mutation (p.Ser518Arg) in ZAP70 kinase: a case-control study

BackgroundThe apparent lack of additional missense mutations data on mixed-phenotype leukemia is noteworthy. Single amino acid substitution by these non-synonymous single nucleotide variations can be related to many pathological conditions and may influence susceptibility to disease. This case-control study aimed to unravel whether the ZAP70 missense variant (rs104893674 (C > A)) underpinning mixed-phenotype leukemia.MethodsThe rs104893674 was genotyped in clients who were mixed-phenotype acute leukemia-, acute lymphoblastic leukemia- and acute myeloid leukemia-positive and matched healthy controls, which have been referred to all major urban hospitals from multiple provinces of country- wide, IRAN, from February 11’ 2019 to June 10’ 2023, by amplification refractory mutation system-polymerase chain reaction method. Direct sequencing for rs104893674 of the ZAP70 gene was performed in a 3130 Genetic Analyzer.ResultsWe found that the AC genotype of individuals with A allele at this polymorphic site (heterozygous variant-type) contribute to the genetic susceptibility to acute leukemia of both forms, acute myeloid leukemia and acute lymphoblastic leukemia as well as with a mixed phenotype. In other words, the ZAP70 missense variant (rs104893674 (C > A)) increases susceptibility of distinct cell populations of different (myeloid and lymphoid) lineages to exhibiting cancer phenotype. The results were all consistent with genotype data obtained using a direct DNA sequencing technique.ConclusionOf special interest are pathogenic missense mutations, since they generate variants that cause specific molecular phenotypes through protein destabilization. Overall, we discovered that the rs104893674 (C > A) variant chance in causing mixed-phenotype leukemia is relatively high.

Assessment of ability of AlphaMissense to identify variants affecting susceptibility to common disease.

An important issue in the analysis of rare variant association studies is the ability to annotate nonsynonymous variants in terms of their likely importance as affecting protein function. To address this, AlphaMissense was recently released and was shown to have good performance using benchmarks based on variants causing severe disease and on functional assays. Here, we assess the performance of AlphaMissense across 18 genes which had previously demonstrated association between rare coding variants and hyperlipidaemia, hypertension or type 2 diabetes. The strength of evidence in favour of association, expressed as the signed log p value (SLP), was compared between AlphaMissense and 43 other annotation methods. The results demonstrated marked variability between genes regarding the extent to which nonsynonymous variants contributed to evidence for association and also between the performance of different methods of annotating the nonsynonymous variants. Although AlphaMissense produced the highest SLP on average across genes, it produced the maximum SLP for only 4 genes. For some genes, other methods produced a considerably higher SLP and there were examples of genes where AlphaMissense produced no evidence for association while another method performed well. The marked inconsistency across genes means that it is difficult to decide on an optimal method of analysis of sequence data. The fact that different methods perform well for different genes suggests that if one wished to use sequence data for individual risk prediction then gene-specific annotation methods should be used.

Genetic associations with human longevity are enriched for oncogenic genes.

Human lifespan is shaped by both genetic and environmental exposures and their interaction. To enable precision health, it is essential to understand how genetic variants contribute to earlier death or prolonged survival. In this study, we tested the association of common genetic variants and the burden of rare non-synonymous variants in a survival analysis, using age-at-death (N = 35,551, median [min, max] = 72.4 [40.9, 85.2]), and last-known-age (N = 358,282, median [min, max] = 71.9 [52.6, 88.7]), in European ancestry participants of the UK Biobank. The associations we identified seemed predominantly driven by cancer, likely due to the age range of the cohort. Common variant analysis highlighted three longevity-associated loci: APOE, ZSCAN23, and MUC5B. We identified six genes whose burden of loss-of-function variants is significantly associated with reduced lifespan: TET2, ATM, BRCA2, CKMT1B, BRCA1 and ASXL1. Additionally, in eight genes, the burden of pathogenic missense variants was associated with reduced lifespan: DNMT3A, SF3B1, CHL1, TET2, PTEN, SOX21, TP53 and SRSF2. Most of these genes have previously been linked to oncogenic-related pathways and some are linked to and are known to harbor somatic variants that predispose to clonal hematopoiesis. A direction-agnostic (SKAT-O) approach additionally identified significant associations with C1orf52, TERT, IDH2, and RLIM, highlighting a link between telomerase function and longevity as well as identifying additional oncogenic genes. Our results emphasize the importance of understanding genetic factors driving the most prevalent causes of mortality at a population level, highlighting the potential of early genetic testing to identify germline and somatic variants increasing one's susceptibility to cancer and/or early death.

Genome wide association study of clinical duration and age at onset of sporadic CJD.

Human prion diseases are rare, transmissible and often rapidly progressive dementias. The most common type, sporadic Creutzfeldt-Jakob disease (sCJD), is highly variable in clinical duration and age at onset. Genetic determinants of late onset or slower progression might suggest new targets for research and therapeutics. We assembled and array genotyped sCJD cases diagnosed in life or at autopsy. Clinical duration (median:4, interquartile range (IQR):2.5-9 (months)) was available in 3,773 and age at onset (median:67, IQR:61-73 (years)) in 3,767 cases. Phenotypes were successfully transformed to approximate normal distributions allowing genome-wide analysis without statistical inflation. 53 SNPs achieved genome-wide significance for the clinical duration phenotype; all of which were located at chromosome 20 (top SNP rs1799990, pvalue = 3.45x10-36, beta = 0.34 for an additive model; rs1799990, pvalue = 9.92x10-67, beta = 0.84 for a heterozygous model). Fine mapping, conditional and expression analysis suggests that the well-known non-synonymous variant at codon 129 is the obvious outstanding genome-wide determinant of clinical duration. Pathway analysis and suggestive loci are described. No genome-wide significant SNP determinants of age at onset were found, but the HS6ST3 gene was significant (pvalue = 1.93 x 10-6) in a gene-based test. We found no evidence of genome-wide genetic correlation between case-control (disease risk factors) and case-only (determinants of phenotypes) studies. Relative to other common genetic variants, PRNP codon 129 is by far the outstanding modifier of CJD survival suggesting only modest or rare variant effects at other genetic loci.

Genetic change investigation in DOCK1 gene in an Iranian family with sign and symptoms of temporomandibular joint disorder (TMD).

Temporomandibular joint disorder (TMD) is a complex condition with pain and dysfunction in the temporomandibular joint and related muscles. Scientific evidence indicates both genetic and environmental factors play a crucial role in TMD. In this study, we aimed to discover the genetic changes in individuals from 4 generations of an Iranian family with signs and symptoms of TMD and malocclusion Class III. Whole Exome Sequencing (WES) was performed in 4 patients (IV-8, IV-9, V-4, and V-6) with TMD according to (DC/TMD), along with skeletal Class III malocclusion. Then, PCR sequencing was performed on 23 family members to confirm the WES. In the present study, WES results analysis detected 6 heterozygous non-synonymous Single Nucleotide Variants (SNVs) in 5 genes, including CRLF3, DNAH17, DOCK1, SEPT9, and VWDE. A heterozygous variant, c.2012T > A (p.F671Y), in Exon 20 of the DOCK1 (NM_001290223.2) gene was identified. Then, this variant was investigated in 19 other members of the same family. PCR-Sequencing results showed that 7/19 had heterozygous TA genotype, all of whom were accompanied by malocclusion and TMD symptoms and 12/19 individuals had homozygous TT genotype, 9 of whom had no temporomandibular joint problems or malocclusion. The remaining 3 showed mild TMD clinical symptoms. The 5 other non-synonymous SNVs of CRLF3, DNAH17, SEPT9, and VWDE were not considered plausible candidates for TMD. The present study identified a heterozygous nonsynonymous c.2012T > A (p.F671Y) variant of the DOCK1 gene is significantly associated with skeletal class III malocclusion, TMD, and its severity in affected individuals in the Iranian pedigree. The role of genetic factors in the development of TMD has been described. The present study identified a nonsynonymous variant of the DOCK1 gene as a candidate for TMD and skeletal class III malocclusion in affected individuals in the Iranian pedigree.

Artificial Intelligence-Driven Prediction Revealed CFTR Associated with Therapy Outcome of Breast Cancer: A Feasibility Study.

In silico tools capable of predicting the functional consequences of genomic differences between individuals, many of which are AI-driven, have been the most effective over the past two decades for non-synonymous single nucleotide variants (nsSNVs). When appropriately selected for the purpose of the study, a high predictive performance can be expected. In this feasibility study, we investigate the distribution of nsSNVs with an allele frequency below 5%. To classify the putative functional consequence, a tier-based filtration led by AI-driven predictors and scoring system was implemented to the overall decision-making process, resulting in a list of prioritised genes. The study has been conducted on breast cancer patients of homogeneous ethnicity. Germline rare variants have been sequenced in genes that influence pharmacokinetic parameters of anticancer drugs or molecular signalling pathways in cancer. After AI-driven functional pathogenicity classification and data mining in pharmacogenomic (PGx) databases, variants were collapsed to the gene level and ranked according to their putative deleterious role. In breast cancer patients, seven of the twelve genes prioritised based on the predictions were found to be associated with response to oncotherapy, histological grade, and tumour subtype. Most importantly, we showed that the group of patients with at least one rare nsSNVs in cystic fibrosis transmembrane conductance regulator (CFTR) had significantly reduced disease-free (log rank, p = 0.002) and overall survival (log rank, p = 0.006). AI-driven in silico analysis with PGx data mining provided an effective approach navigating for functional consequences across germline genetic background, which can be easily integrated into the overall decision-making process for future studies. The study revealed a statistically significant association with numerous clinicopathological parameters, including treatment response. Our study indicates that CFTR may be involved in the processes influencing the effectiveness of oncotherapy or in the malignant progression of the disease itself.

Genetic link between KIF1A mutations and amyotrophic lateral sclerosis: evidence from whole-exome sequencing.

Genetics have been shown to have a substantial impact on amyotrophic lateral sclerosis (ALS). The ALS process involves defects in axonal transport and cytoskeletal dynamics. It has been identified that KIF1A, responsible for encoding a kinesin-3 motor protein that carries synaptic vesicles, is considered a genetic predisposing factor for ALS. The analysis of whole-exome sequencing data from 1,068 patients was conducted to examine the genetic link between ALS and KIF1A. For patients with KIF1A gene mutations and a family history, we extended the analysis to their families and reanalyzed them using Sanger sequencing for cosegregation analysis. In our cohort, the KIF1A mutation frequency was 1.31% (14/1,068). Thirteen nonsynonymous variants were detected in 14 ALS patients. Consistent with the connection between KIF1A and ALS, the missense mutation p.A1083T (c.3247G>A) was shown to cosegregate with disease. The mutations related to ALS in our study were primarily located in the cargo-binding region at the C-terminal, as opposed to the mutations of motor domain at the N-terminal of KIF1A which were linked to hereditary peripheral neuropathy and spastic paraplegia. We observed high clinical heterogeneity in ALS patients with missense mutations in the KIF1A gene. KIF5A is a more frequent determinant of ALS in the European population, while KIF1A accounts for a similar proportion of ALS in both the European and Chinese populations. Our investigation revealed that mutations in the C-terminus of KIF1A could increase the risk of ALS, support the pathogenic role of KIF1A in ALS and expand the phenotypic and genetic spectrum of KIF1A-related ALS.