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At least 19 recordsLinked to original sources
PubMed2026

The Role of Small Segmental Duplications in Generating Identical Isoforms Through Alternative Splicing Sites.

Alternative splicing plays a crucial role in expanding proteomic diversity but can also generate identical isoforms under certain conditions. While mutually exclusive splicing of tandem exons has occasionally been reported to produce identical isoforms, the extent to which other splicing events contribute to this phenomenon remains unclear. In this study, we demonstrate that alternative 5' and 3' splice site selection can also lead to the formation of identical isoforms, providing an additional type of splicing event for functional redundancy in transcriptomes. To address this, we analyzed reference genome annotations from 15 plant species, including Arabidopsis thaliana and wheat (Triticum aestivum), obtained from the RefSeq database. Identical isoforms were computationally defined as transcripts with distinct exon-intron structures but identical coding sequences. Our analysis reveals that the majority of alternative 5' and 3' fragments originate from small segmental duplications, suggesting that sequence repetition within gene regions facilitates the emergence of such splicing patterns. We also observed differences in the annotated 5' UTRs of some identical isoforms. However, since the alternative splicing sites themselves were not located within UTRs, these differences may reflect annotation uncertainty rather than genuine AS-derived variation. Given that UTR predictions in reference databases are not always precise, such observations should be interpreted cautiously. Expression analysis using an isoform-specific k-mer approach confirmed that identical isoforms can be differentially regulated. These findings suggest that, beyond expanding protein diversity, alternative splicing can also generate redundant isoforms that are differentially expressed at the RNA level, indicating potential regulatory roles. By elucidating the structural and regulatory factors contributing to the formation and retention of identical isoforms, our study provides new insights into the evolutionary and functional significance of alternative splicing in plants.

Alternative Splicing↗
PubMed2026

Functional Validation of a Novel Homozygous TTN Splice-Site Variant Reveals Aberrant Splicing in Hypertrophic Cardiomyopathy.

The TTN gene encodes a crucial structural protein within cardiac sarcomeres, and its variants may contribute to hypertrophic cardiomyopathy (HCM) and dilated cardiomyopathy; however, phenotype and genotype are different. Whole-exome sequencing (WES) was conducted on a Chinese proband diagnosed with HCM. In silico splicing prediction tools and minigene assays were employed to investigate the impact of the identified variant on mRNA splicing. A literature review was performed to retrieve and analyze previously reported splicing variants in the TTN gene associated with HCM. A 42-year-old male proband presented with nonobstructive HCM and paroxysmal atrial arrhythmias. A novel homozygous TTN variant was found, predicted to cause a 14-base pair deletion at a splice acceptor site. Two asymptomatic offspring were found to carry the heterozygous variant. Based on variant interpretation guidelines, the variant met the PM2_supporting criterion and was classified as a variant of uncertain significance (VUS). The predicted aberrant splicing effect was subsequently confirmed by the minigene splicing assay, demonstrating altered pre-mRNA splicing leading to an in-frame insertion/deletion (p.Arg32498_Glu32504delinsGln). Functional verification confirmed that this mutation conforms to the PM4 criterion, suggesting that it can be reclassified as a tepid VUS (scoring 3 points). The functional result might provide pathogenic evidence. We also reviewed 28 previously reported splicing variants in TTN associated with HCM. Of these, 57.1% (16/28) localized to the I-band region, whereas 21.4% (6/28) were situated in the A-band domain of titin. Notably, 21.4% (6/28) co-occurred with pathogenic variants in other sarcomeric genes (MYH7 or MYBPC3), correlating with more severe clinical phenotypes. Reclassification and reinterpretation of the variants revealed that none met the level of likely pathogenic or higher. The present case contributes a homozygous splice-site variant with experimentally confirmed aberrant splicing and an in-frame protein alteration in titin. The focus of this report is the Mendelian genetic basis of the proband's cardiomyopathy phenotype, and our data provide additional case-level and functional evidence for a possible role of specific TTN splicing defects in HCM.

Humans↗
PubMed2026

Pervasive noise in human pre-mRNA splice site selection.

RNA splicing has historically been thought to be highly efficient and accurate, with little opportunity for deviation from regulated alternative splicing. This dogma has been challenged by recent observations that biological noise may contribute substantially to transcriptome diversity. However, quantitative understanding of stochastic splicing variation is challenging because these transcripts are likely subject to rapid degradation. Here, we use deep sequencing across RNA compartments to track splicing intermediates in human cells and see abundant cryptic splicing associated with genomic features that promote splicing noise. We observe pervasive usage of low-fidelity splice sites, likely due to stochasticity in recruitment or binding of the spliceosome. These sites are turned over quickly and show evidence for nuclear and cytoplasmic degradation, suggesting widespread surveillance and rapid quality control of non-productive transcripts. Our findings provide insights into the propensity for error in RNA processing mechanisms and regulation of alternative splice sites across a gene.

Humans↗
PubMed2025

Pervasive noise in human splice site selection.

RNA splicing has historically been thought to be highly efficient and accurate, with little opportunity for deviation from regulated alternative splicing decisions. This dogma has been challenged by recent observations that suggest that biological noise may contribute substantially to transcriptome diversity. However, quantitative understanding of stochastic variations in splicing is challenging because these transcripts are likely subject to rapid degradation. Here, we use ultra-deep sequencing across RNA compartments to track splicing intermediates in human cells and see abundant cryptic splicing associated with genomic features that promote splicing noise. We observe pervasive usage of low-fidelity splice sites, likely due to stochasticity in recruitment or binding of the spliceosome. These sites are most likely degraded in the nucleus rather than targeted by translation-dependent degradation processes, suggesting widespread surveillance and rapid quality control of non-productive RNA transcripts. Our findings provide unprecedented insights into the propensity for error in RNA processing mechanisms and the regulation of alternative splice sites across a gene.

Journal Article↗
PubMed2025

Precursor RNA structural patterns at SF3B1 mutation sensitive cryptic 3' splice sites.

SF3B1 is a core component of the spliceosome involved in branch point recognition and 3' splice site selection. The SF3B1 K700E mutation (lysine to glutamic acid) is common in myelodysplastic syndrome and other blood disorders. SF3B1 K700E mutants utilize novel cryptic 3' splice sites; however, the properties distinguishing SF3B1-sensitive splice junctions from other alternatively spliced junctions are unknown. We identify a subset of 192 cryptic 3' splice junctions with significantly altered use in SF3B1 K700E cells, termed SF3B1-sensitive cryptic 3' splice sites, and 2800 cryptic 3' splice sites used in SF3B1 wild-type, termed SF3B1-resistant. We find that SF3B1-sensitive cryptic 3' splice sites are embedded in extended polypyrimidine tracts. Furthermore, canonical splice sites paired to SF3B1-sensitive cryptic 3' splice sites are significantly weaker than canonical 3' splice sites paired to SF3B1-resistant cryptic 3' splice sites. We test whether SF3B1-sensitive splice sites are structurally different from SF3B1-resistant 3' splice sites using chemical probing. We develop experimental RNA structure data for 83 SF3B1-sensitive junctions and 39 SF3B1-resistant junctions. We find that the pattern of structural accessibility at the NAG splicing motif in cryptic and canonical 3' splice sites is similar. However, the magnitude of accessibility differences is less in paired SF3B1-sensitive splice sites than in paired SF3B1-mutant splice sites. Additionally, SF3B1-sensitive splice junctions are more flexible than SF3B1-resistant junctions. Our results suggest that SF3B1-sensitive splice junctions have unique structure and sequence properties, containing poorly differentiated, weak splice sites that lead to altered 3' splice site recognition in the presence of SF3B1 mutation.

RNA Splicing Factors↗
PubMed2025

Improving spliced alignment by modeling splice sites with deep learning.

MOTIVATION: Spliced alignment refers to the alignment of messenger RNA (mRNA) or protein sequences to eukaryotic genomes. It plays a critical role in gene annotation and the study of gene functions. Accurate spliced alignment demands sophisticated modeling of splice sites, but current aligners use simple models, which may affect their accuracy given dissimilar sequences. RESULTS: We implemented minisplice to learn splice signals with a one-dimensional convolutional neural network (1D-CNN) and trained a model with 7,026 parameters for vertebrate and insect genomes. It captures conserved splice signals across phyla and reveals GC-rich introns specific to mammals and birds. We used this model to estimate the empirical splicing probability for every GT and AG in genomes, and modified minimap2 and miniprot to leverage pre-computed splicing probability during alignment. Evaluation on human long-read RNA-seq data and cross-species protein datasets showed our method greatly improves the junction accuracy especially for noisy long RNA-seq reads and proteins of distant homology. AVAILABILITY AND IMPLEMENTATION: https://github.com/lh3/minisplice.

Journal Article↗
PubMed2026

Novel splice-site and recurrent p.Arg729* CNKSR2 variants in ESES/CSWS: insights into sex-dependent expression.

PURPOSE: Pathogenic variants in CNKSR2 (Xp22.12) cause an X-linked neurodevelopmental disorder with intellectual disability, language impairment, and a distinctive epilepsy phenotype, including encephalopathy with status epilepticus during slow-wave sleep (ESES/CSWS). Hemizygous males are typically severely affected, whereas symptomatic females remain rare and incompletely characterized. We describe two unrelated patients with de novo CNKSR2 variants to expand the mutational and sex-dependent phenotypic spectrum of this disorder. METHODS: Both patients underwent clinical, electroencephalographic, and neuroimaging evaluation. CNKSR2 variants were identified by whole exome sequencing with parental segregation, and the splice-site variant was assessed in silico (SpliceAI, MaxEntScan, Human Splicing Finder). RESULTS: Patient 1, a 17-year-old female, harbored a novel canonical splice-site variant (c.64+1G>A) in the N-terminal region and presented with a relatively mild phenotype. In silico analysis supported abolition of the canonical donor splice site. Patient 2, an 8-year-old male, carried a de novo nonsense variant (c.2185C>T, p.Arg729*) and exhibited drug-resistant ESES, autism, and severe language impairment. p.Arg729* had previously been reported in one independent male. Our case represents its second independent occurrence, a CGA>TGA transition at a CpG dinucleotide consistent with a mutational hotspot. CONCLUSION: Together, these cases expand the mutational spectrum and provide further evidence for sex-dependent phenotypic variability in CNKSR2-related epilepsy. Our observations support the hypothesis that X-chromosome inactivation may contribute to phenotypic variability in females, although XCI was not assessed here, and support inclusion of CNKSR2 in epilepsy gene panels regardless of sex.

Humans↗
PubMed2026

Novel splice site variants in GBA1 are associated with Gaucher disease and genotype-phenotype correlations.

BACKGROUND: Variants in GBA1 are associated with neurodegenerative disease. This study aimed to explore pathogenic GBA1 variants. METHODS: Four patients with progressive myoclonic epilepsy (PME) and extremely low β-glucosidase levels were recruited. Whole-exome sequencing and long-range PCR were performed to identify GBA1 variants. Bioinformatic analyses were used to predict the impact of the identified variants. A literature review was performed to explore the genotype-phenotype correlations. GBA1 expression data across different brain regions and developmental stages were analyzed using the BrainSpan database. RT-PCR was performed to verify the splicing effects. RESULTS: Compound heterozygous GBA1 variants were identified in four patients. Five distinct variants were detected, including two novel splice site variants (c.308-2A>G and c.762-2A>C) and three previously reported variants. All identified variants were rare or absent in gnomAD. Splice site variants c.308-2A>G and c.762-2A>C were predicted to cause aberrant splicing. Minigene-based splicing assays coupled with RT-PCR and Sanger sequencing confirmed that both variants cause complete exon skipping (exon 4 and exon 7, respectively). All patients presented with PME onset in childhood/adolescence, intellectual regression, low β-glucosidase, and diffuse brain atrophy and were subsequently diagnosed with Gaucher disease type 3. GBA1 expression in the brain showed two distinct peaks: one in infancy and another after five years of age. The onset age of PME aligned with the second GBA1 expression peak (after five years of age). CONCLUSION: This study identified compound heterozygous GBA1 variants, including two novel candidate pathogenic splice site variants, in Gaucher disease type 3 patients, expanding the known mutational spectrum.

Humans↗
PubMed2026

Identification of a Novel Splice-Site variant in TACR3 (c.888 + 1G > A) Associated with Asthenozoospermia and Hypogonadotropic Hypogonadism in an Iranian Family.

BACKGROUND: TACR3 encodes the receptor for neurokinin B, a key regulator of the hypothalamic-pituitary-gonadal axis. Disruption of this pathway can impair gonadotropin release and male reproductive function. Given the genetic heterogeneity of male infertility, this study aimed to identify novel variants in TACR3 that may underlie asthenozoospermia and related hormonal abnormalities. METHODS: Fifteen infertile men with confirmed asthenozoospermia were enrolled. Whole-exome sequencing (WES) was performed on genomic DNA from peripheral blood, and the candidate variant was validated by Sanger sequencing. Functional predictions were made using PolyPhen-2, SIFT, MutationTaster, and REVEL. TACR3 mRNA expression levels were assessed by real-time PCR in available samples. RESULTS: A novel splice-site variant, TACR3 (NM_001059.3:c.888 + 1G > A), was detected and found to segregate with infertility in one family, appearing homozygously in two infertile brothers and heterozygously in the proband with severe asthenozoospermia. The variant was absent in public and local genomic databases, suggesting its extremely rare frequency. Furthermore, RT-PCR showed a dramatic reduction or complete loss of TACR3 expression in affected individuals, confirming its deleterious effect on splicing and mRNA stability. CONCLUSION: We identified a previously unreported splice-site mutation in TACR3 (c.888 + 1G > A) that likely causes familial infertility by disrupting the neurokinin B/NK3R signaling pathway. While the heterozygous proband exhibited severe asthenozoospermia, the homozygous brothers displayed hormonal profiles typical of hypogonadotropic hypogonadism. These findings extend the mutational landscape of TACR3 and highlight its essential contribution to male reproductive endocrinology.

Humans↗
PubMed2025

Identification of a novel RBCK1 splice site donor variant in Basset Hounds with glycogen storage disease myopathy.

Glycogen storage diseases (GSDs) are rare, typically inherited, disorders caused by various defects in glycogen metabolism enzymes, generally resulting in the accumulation of glycogen in several tissues. Recently, two young adult Basset Hound (BH) littermates were diagnosed with GSD via postmortem histopathology, with excess glycogen manifesting in both cardiac and smooth muscle. Using whole genome sequencing, a homozygous splice site donor variant was identified in exon 8 of RBCK1, a gene which encodes an E3 ubiquitin ligase, in both littermates, suggesting an autosomal recessive mode of inheritance. The presumptive loss of the splice site donor is predicted to result in premature termination in the mid-domain of the protein. Screening for the variant in related (n = 21) and unrelated (n = 124) BHs identified one additional affected littermate and nine familial heterozygous carriers. No variant alleles were present in the unrelated BH population, establishing the novelty of the identified mutation. RBCK1 variants have previously been associated with polyglucosan body myopathy type 1 (PGBM1), a type of GSD characterized by skeletal muscle myopathy, cardiomyopathy, and polyglucosan accumulation in humans. To date, no reported variants in RBCK1 have been identified in dogs or other large animals associated with GSD, making this the first naturally occurring large animal model of PGBM1 due to an RBCK1 defect.

Animals↗
PubMed2024

A germline PDGFRB splice site variant associated with infantile myofibromatosis and resistance to imatinib.

PURPOSE: Infantile myofibromatosis is characterized by the development of myofibroblastic tumors in young children. In most cases, the disease is caused by somatic gain-of-function variants in platelet-derived growth factor (PDGF) receptor beta (PDGFRB). Here, we reported a novel germline intronic PDGFRB variant, c.2905-8G>A, in 6 unrelated infants with multifocal myofibromatosis and their relatives. METHODS: We performed constitutional and tumor DNA and RNA sequencing to identify novel variants, which were subsequently characterized in cellular assays. RESULTS: All patients had multiple skin nodules, 4 had bone lesions, and 2 had aggressive disease with bowel obstruction. The c.2905-8G>A substitution creates an alternative acceptor splice site in intron 21, inserting 2 codons in the PDGFRB transcript. Functional studies revealed that the splice change induced a partial loss of function, contrasting with previously described variants. In 4 tumor samples, we identified a second somatic hit at position Asp850 in PDGFRB exon 18, triggering constitutive receptor activation and resistance to imatinib. In addition to vinblastine and methotrexate, 2 patients received imatinib without objective response. One of them switched to dasatinib with concomitant improvement. CONCLUSION: This splice-site PDGFRB variant favors the development of myofibroma, featuring an acquired oncogenic variant in the same gene and resistance to targeted therapy.

Humans↗
PubMed2025

Exome sequencing identifies a homozygous splice site variant in RP1 as the underlying cause of autosomal recessive retinitis pigmentosa in a Pakistani family.

BACKGROUND: Mutations in RP1 gene are the third leading cause of inherited retinal dystrophies (IRDs) in Pakistani families. PATIENTS: A two-generation consanguineous Pakistani family underwent both clinical and genetic analyses. Clinical examinations included visual acuity test, visual field, fundoscopy, and ocular coherence tomography (OCT). Whole exome sequencing (WES) was performed on the proband's DNA, and Sanger sequencing was performed to validate the WES findings. Splicing prediction tools such as Human Splicing Finder (HSF), NNSplice predictor, SpliceAI, MaxENTScan, and SpliceRover were used. RESULTS: A nuclear family of seven children, comprising five affected individuals (four males and one female) and two healthy siblings, was recruited from northwestern Pakistan. The proband was a 49-years old male who was presented with complaints of decreased visual acuity and night blindness since early childhood. Upon clinical evaluation, the proband appeared to have severely reduced visual acuity of hand movement (HM), bilateral visual field constriction, a waxy pale disc with vascular attenuation, pigmentary bone spicules at the periphery associated with chorioretinal degeneration, diffuse macular atrophy, and horizontal nystagmus in both of his eyes. Exome sequencing (ES) in the proband identified a homozygous splice site variant (NM_006269.2: c.615 + 1G > A) in RP1 gene. In-silico analysis, genotype-phenotype co-segregation study, and literature survey strongly supported the causality of the detected variant. CONCLUSIONS: We report a previously known pathogenic splice site variant of RP1 as the underlying cause of early-onset autosomal recessive retinitis pigmentosa (arRP) in a Pakistani family. We contemplate that the detected allele might constitute a mutational hotspot in RP1.

Humans↗
PubMed2025

EZH2 variants derived from cryptic splice sites govern distinct epigenetic patterns during embryonic development.

EZH2 catalyzes H3K27me3 and is essential for embryonic development. Although multiple EZH2 variants have been identified, the functional implications and physiological significance of its heterogeneity remain unclear. Here, we revealed that conserved cryptic splice sites generated two EZH2 variants with (EZH2A) or without (EZH2B) a 27-nt region, coding for a 9-aa segment. Structural modeling showed that splice-in or splice-off of the 9-aa segment caused a topological change in EZH2 structure. The 9-aa surplus in EZH2A strengthened its interaction with other PRC2 components, particularly in PRC2.2 holocomplex. We developed point-mutation mouse lines specifically depleting EZH2A or EZH2B (Ezh2amut or Ezh2bmut). Biallelic deletion of Ezh2a caused developmental defects and embryonic lethality between E12.5 and E15.5, while the Ezh2bmut mice were fertile and developed normally. Combined RNA-seq and CUT&Tag analyses in mouse embryonic fibroblasts revealed that EZH2A and EZH2B bound to different genomic loci and affected H3K27me3 deposition in different subsets of genes related to development or the innate immune system, respectively. EZH2A depletion specifically suppressed the expression of genes involved in the development-related Hippo-Yap1 pathway, which might be attributable to a compensatory process mediated by JARID2. Our findings demonstrate that EZH2 heterogeneity from the 9-aa splicing event plays a crucial role in development.

Animals↗
PubMed2026

Gastrointestinal involvement in Ehlers-Danlos syndrome classical-like type 2 associated with a novel AEBP1 splice-site variant.

Ehlers-Danlos syndrome classical-like type 2 (clEDS2) is a rare autosomal recessive connective tissue disorder caused by biallelic loss-of-function variants in the gene encoding adipocyte enhancer-binding protein 1 (AEBP1). While cutaneous and skeletal manifestations are commonly observed, gastrointestinal complications, including bowel rupture, have been reported only rarely, and their histopathological basis remains poorly characterized. Here, we report findings of molecular investigations, gastrointestinal histopathological evaluation, and long-term clinical follow-up in the 16th reported patient with AEBP1-related clEDS2, complicated by spontaneous bowel perforation. A homozygous AEBP1 splice-site variant (NM_001129.5:c.1401-2 A > G) was identified by a custom next-generation sequencing-based panel analysis for hereditary connective tissue disorders. Transcript-level analysis by reverse transcription-polymerase chain reaction and Sanger sequencing demonstrated complete skipping of exon 12, resulting in a frameshift and predicted loss of function. Clinically, the patient experienced postoperative perforation in the sigmoid colon shortly after rectal cancer surgery, followed nearly 20 years later by spontaneous small intestinal perforation. Histopathological examination of the affected colonic tissue demonstrated mildly widened intermuscular spaces without other overt structural abnormalities. Notably, repeated upper and lower gastrointestinal endoscopic procedures were performed during long-term oncological surveillance without procedure-related bowel perforation. This observation could offer an opportunity to learn about gastrointestinal involvement in AEBP1-related clEDS2 and suggests that its gastrointestinal manifestations may differ in clinical context from those typically associated with vascular Ehlers-Danlos syndrome, warranting further investigation as additional cases are accumulated.

Humans↗
PubMed2017

OCA2 splice site variant in German Spitz dogs with oculocutaneous albinism.

We investigated a German Spitz family where the mating of a black male to a white female had yielded three puppies with an unexpected light brown coat color, lightly pigmented lips and noses, and blue eyes. Combined linkage and homozygosity analysis based on a fully penetrant monogenic autosomal recessive mode of inheritance identified a critical interval of 15 Mb on chromosome 3. We obtained whole genome sequence data from one affected dog, three wolves, and 188 control dogs. Filtering for private variants revealed a single variant with predicted high impact in the critical interval in LOC100855460 (XM_005618224.1:c.377+2T>G LT844587.1:c.-45+2T>G). The variant perfectly co-segregated with the phenotype in the family. We genotyped 181 control dogs with normal pigmentation from diverse breeds including 22 unrelated German Spitz dogs, which were all homozygous wildtype. Comparative sequence analyses revealed that LOC100855460 actually represents the 5'-end of the canine OCA2 gene. The CanFam 3.1 reference genome assembly is incorrect and separates the first two exons from the remaining exons of the OCA2 gene. We amplified a canine OCA2 cDNA fragment by RT-PCR and determined the correct full-length mRNA sequence (LT844587.1). Variants in the OCA2 gene cause oculocutaneous albinism type 2 (OCA2) in humans, pink-eyed dilution in mice, and similar phenotypes in corn snakes, medaka and Mexican cave tetra fish. We therefore conclude that the observed oculocutaneous albinism in German Spitz is most likely caused by the identified variant in the 5'-splice site of the first intron of the canine OCA2 gene.

Albinism, Oculocutaneous↗
PubMed2026

A novel ASCC1 splice-site variant broadens the phenotypic spectrum of spinal muscular atrophy with congenital bone fractures type 2.

Spinal muscular atrophy with congenital bone fractures type 2 (SMABF2) is an ultra-rare neuromuscular disorder caused by pathogenic variants affecting the ASC-1 complex, most commonly ASCC1. The disorder is typically characterized by severe congenital hypotonia, prenatal or congenital fractures, and early respiratory failure. We report a girl with a novel homozygous intronic donor-site variant, c.95+5G>C, in ASCC1. In contrast to the classic SMABF2 phenotype, she had no congenital fractures and survived until 7 years of age. Her clinical presentation included generalized hypotonia, areflexia, minimal spontaneous movements, dysmorphic features related to fetal hypomobility, progressive respiratory insufficiency requiring tracheostomy and gastrostomy, and cardiac involvement. This case expands both the genetic and phenotypic spectrum of ASCC1-associated disease. The comparatively prolonged survival and absence of congenital fractures suggest that not all ASCC1 variants result in a fully loss-of-function phenotype. However, this interpretation remains hypothetical because functional RNA studies were not performed.

Humans↗
PubMed2025

Tandem splice acceptor sites: Profiling their relevance to human disease.

PURPOSE: Interpretation of variation, particularly the creation or disruption of tandem splice acceptor sites (NAGNnAG variants), challenges genomic medicine practice. METHODS: We analyzed the creation and disruption of dinucleotide AG sites within ±30 bases of natural splice-acceptor sites in the GRCh37 human reference genome. These results were compared with variant data from the ClinVar and gnomAD databases, as well as with data from 779 National Institutes of Health Undiagnosed Diseases Program study participants. Using RNA sequencing, we assessed the splicing at NAGNnAG variants for 107 of the Undiagnosed Diseases Program participants and compared the empirical data with SpliceAI predictions. RESULTS: Creation or disruption of NAGNnAG sites within 30 bases of the natural splice acceptor are enriched in ClinVar compared with gnomAD; however, such variants in the 2 databases are rarely differentiated by SpliceAI scores. Empirical evaluation via RNA sequencing analysis supported novel acceptor site usage from -21 to +30; splice-altering variants did not predominate in a specific region or have SpliceAI scores invariantly, suggesting increased spliceogenicity. CONCLUSION: NAGNnAG variants within 30 bp of the natural splice acceptor have a high probability of clinical relevance and are poorly contextualized for clinical utility. Their interpretation benefits from empirical evaluation via RNA analysis.

Humans↗