Pathogenic, criteria provided, single submitter | curation | Broad Center for Mendelian Genomics, Broad Institute of MIT and Harvard | May 02, 2023 | The heterozygous c.258+2T>C variant in SBDS was identified by our study, in the compound heterozygous state along with a pathogenic variant (ClinVar Variation ID: 265256), in one individual with Swachman-Diamond syndrome. This individual also carried a pathogenic variant (ClinVar Variation ID: 265256), however the phase of these variants are unknown at this time. The c.258+2T>C variant in SBDS has been reported in over 108 unrelated individuals with Swachman-Diamond syndrome (PMID: 15769891, PMID: 15860664, PMID: 12496757) but has been identified in 0.8% (88/10582) of European (Finnish) chromosomes by the Genome Aggregation Database (gnomAD, http://gnomad.broadinstitute.org; dbSNP ID: rs113993993); however, this allele frequency may not be accurate due to the presence of a pseudogene (SBDSP). This variant has also been reported in ClinVar (Variation ID: 3196) and has been interpreted as pathogenic by multiple submitters. Of these 108 individuals, 9 were homozygotes (PMID: 15860664, PMID: 12496757, PMID: 15769891) and 97 were compound heterozygotes who carried pathogenic or likely pathogenic variants in trans (PMID: 15769891, ClinVar Variation ID: 3195, ClinVar Variation ID: 21539; PMID: 15860664, ClinVar Variation ID: 929404, ClinVar Variation ID: 3195, ClinVar Variation ID: 265256, PMID: 12496757, ClinVar Variation ID: 3195, ), which increases the likelihood that the c.258+2T>C variant is pathogenic. RT-PCR analysis performed on affected tissue shows evidence of altered splicing of exon 2, with an 8bp deletion, frameshift, and premature protein truncation (PMID: 12496757); in vitro assays suggest that the resulting prematurely truncated protein is unstable (PMID: 17478638). This variant is located in the 5' splice region. Computational tools predict a splicing impact, though this information is not predictive enough to determine pathogenicity. Loss of function is an established disease mechanism of autosomal recessive Swachman-Diamond syndrome. In summary, this variant meets criteria to be classified as pathogenic for autosomal recessive Swachman-Diamond syndrome. ACMG/AMP Criteria applied: PVS1, PS3_Moderate, PM3_VeryStrong (Richards 2015). - |
Pathogenic, criteria provided, single submitter | clinical testing | Suma Genomics, Suma Genomics | - | - - |
Pathogenic, criteria provided, single submitter | clinical testing | Genome Diagnostics Laboratory, University Medical Center Utrecht | Jul 28, 2017 | - - |
Pathogenic, no assertion criteria provided | research | Donald Williams Parsons Laboratory, Baylor College of Medicine | Sep 30, 2015 | This variant has been previously reported as disease-causing. It would be pathogenic in a recessive state; heterozygotes would be carriers for the condition. It was found once in our study heterozygous in a 12-year-old male with pilocytic astrocytoma. - |
Pathogenic, no assertion criteria provided | literature only | OMIM | Aug 15, 2007 | - - |
Pathogenic, criteria provided, single submitter | clinical testing | Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine | Dec 03, 2018 | The c.258+2T>C variant in SBDS is one of the most common pathogenic variants ide ntified in individuals with Shwachman-Diamond syndrome (Boocock 2003, https://ww w.ncbi.nlm.nih.gov/books/NBK1756/). It has also been identified in 0.9% (236/250 74) of Finnish chromosomes and 2 homozygotes by gnomAD (http://gnomad.broadinsti tute.org); however, this allele frequency may not be accurate due to the presenc e of a pseudogene (SBDSP). This variant usually occurs as the result of a gene c onversion event as the c.258+2C>T variant is present in the inactive pseudogene. It is predicted to result in a frameshift described as p.Cys84TyrfsX4 (Boocock 2003, Orelio 2011). This alteration is then predicted to lead to a truncated or absent protein. Loss of function of the SBDS gene is an established disease mech anism in autosomal recessive Shwachman-Diamond syndrome. In summary, this varian t meets criteria to be classified as pathogenic. ACMG/AMP Criteria applied: PVS1 , PM3_Very Strong, PS3. - |
Pathogenic, no assertion criteria provided | curation | Reproductive Health Research and Development, BGI Genomics | Jan 06, 2020 | NG_007277.1(NM_016038.2):c.258+2T>C in the SBDS gene has an allele frequency of 0.009 in European (Finnish) subpopulation in the gnomAD database. Andolina JR et al. identified compound heterozygous mutations c183_184 TA>CT and c.258+2 T>C in two patients with Shwachman-Diamond syndrome (PMID: 22935661). Taken together, we interprete this variant as Pathogenic/Likely pathogenic. ACMG/AMP Criteria applied: PVS1; PM3; PP4. - |
Likely pathogenic, no assertion criteria provided | research | NIHR Bioresource Rare Diseases, University of Cambridge | - | - - |
Pathogenic, criteria provided, single submitter | clinical testing | Lifecell International Pvt. Ltd | - | A Heterozygous Splice site donor variant c.258+2T>C in Exon 2 of the SBDS gene that results in the amino acid substitution was identified. The observed variant has a minor allele frequency of 0.00388/0.00386 in gnomAD exomes and genomes, respectively. The severity of the impact of this variant on the protein is high, based on the effect of the protein and REVEL score . Rare Exome Variant Ensemble Learner (REVEL) is an ensembl method for predicting the pathogenicity of missense variants based on a combination of scores from 13 individual tools: MutPred, FATHMM v2.3, VEST 3.0, PolyPhen-2, SIFT, PROVEAN, MutationAssessor, MutationTaster, LRT, GERP++, SiPhy, phyloP, and phastCons. The REVEL score for an individual missense variant can range from 0 to 1, with higher scores reflecting greater likelihood that the variant is disease-causing. ClinVar has also classified this variant as Pathogenic/Likely Pathogenic [Variant ID: 3196]. This varaint is reported for Shwachman-Diamond syndrome and functional studies suggest that the c.258+2 T>C variant affects the protein's cellular localization and motility (Orelio C et . al., 2011). For these reasons, this variant has been classified as Pathogenic. - |
Pathogenic, criteria provided, single submitter | clinical testing | Institute of Human Genetics, University of Leipzig Medical Center | Dec 16, 2021 | This variant was identified as homozygous._x000D_ Criteria applied: PVS1, PS3, PS4 - |
Pathogenic, criteria provided, single submitter | clinical testing | Institute of Human Genetics Munich, Klinikum Rechts Der Isar, TU München | Dec 16, 2021 | - - |
Pathogenic, criteria provided, single submitter | case-control | Genetics Laboratory, Department of Biology, Semnan University | Dec 30, 2020 | The identified mutation changes the splicing process of SBDS gene. - |
Pathogenic, criteria provided, single submitter | clinical testing | Laboratory of Medical Genetics, National & Kapodistrian University of Athens | Oct 01, 2021 | PVS1, PP2, PP5 - |
Likely pathogenic, criteria provided, single submitter | research | Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center | Mar 17, 2024 | - - |
Pathogenic, criteria provided, single submitter | clinical testing | Victorian Clinical Genetics Services, Murdoch Childrens Research Institute | Jul 17, 2023 | Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with Shwachman-Diamond syndrome (MIM#260400). (I) 0106 - This gene is associated with autosomal recessive disease. (I) 0115 - Variants in this gene are known to have variable expressivity. A phenotypic spectrum with variable severity was observed in a cohort study. In addition, two unrelated asymptomatic individuals were later diagnosed with mild Shwachmann-Diamond syndrome following genetic investigations due to family history and clinical follow-ups (PMID: 24388329) . (I) 0210 - Splice site variant proven to affect splicing of the transcript with a known effect on protein sequence. RT-PCR analysis of patient cells showed an 8bp deletion at the end of exon 2 consistent with the use of an upstream cryptic splice donor site. The deletion results in a frameshift and a premature termination codon, p.(Cys84Tyrfs*4) (PMID: 12496757, 15860664). (SP) 0252 - This variant is homozygous. (I) 0304 - Variant is present in gnomAD (v2) <0.01 for a recessive condition (1092 heterozygotes, 2 homozygotes). (SP) 0311 - Alternative nucleotide changes at the same canonical splice site are present in gnomAD (v2 & v3) (highest allele count: 3 heterozygotes, 0 homozygotes). (I) 0801 - This variant has very strong previous evidence of pathogenicity in unrelated individuals. It has been previously reported as pathogenic in many patients with Shwachman-Diamond syndrome and is one of the most common pathogenic variants in cases of SBDS [ClinVar, PMIDs: 12496757, 32150944, Nelson and Myers (2018)]. (SP) 1201 - Heterozygous variant detected in trans with a second pathogenic heterozygous variant, NM_016038.2(SBDS):c.183_184delinsCT; p.(Lys62*), in a recessive disease. (SP) 1209 - This variant has been shown to be both maternally and paternally inherited (biallelic) (Sanger analysis). (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign - |
Pathogenic, criteria provided, single submitter | clinical testing | Women's Health and Genetics/Laboratory Corporation of America, LabCorp | Feb 08, 2024 | Variant summary: SBDS c.258+2T>C is located in a canonical splice-site and is predicted to affect mRNA splicing resulting in a significantly altered protein due to either exon skipping, shortening, or inclusion of intronic material. Several computational tools predict a significant impact on normal splicing: Three predict the variant abolishes the canonical 5' splicing donor site and three predict the variant creates/strengthens a cryptic 5' donor site. At least one publication reports experimental evidence that this variant indeed affects mRNA splicing and results in the skipping of exon 2 (e.g. Peretto_2023). The variant allele was found at a frequency of 0.0039 in 251238 control chromosomes in the gnomAD database, including 2 homozygotes. However, due to the presence of a SBDS pseudogene, this frequency may be inaccurate, allowing no conclusion about variant significance. c.258+2T>C has been reported in the literature in many individuals affected with Shwachman-Diamond Syndrome 1 and is considered a common disease variant (e.g. Furutani_2022). These data indicate that the variant is very likely to be associated with disease. The following publications have been ascertained in the context of this evaluation (PMID: 36835434, 34758064). ClinVar contains an entry for this variant (Variation ID: 3196). Based on the evidence outlined above, the variant was classified as pathogenic. - |
Pathogenic, criteria provided, single submitter | clinical testing | New York Genome Center | Jul 09, 2020 | - - |
Pathogenic, criteria provided, single submitter | clinical testing | Neuberg Centre For Genomic Medicine, NCGM | - | The splicesite variant has been reported previously in homozygous and compound heterozygous state in individuals with Shwachman-Diamond syndrome Cho WK, et al., 2015. Functional studies suggest that the c.258+2 T>C variant affects theprotein's cellular localization and motility Orelio C, et al., 2011. The variant is reported with 0.3% allele frequency in gnomADExomes and is novel not in any individuals in 1000 Genomes. This variant has been reported to the ClinVar database as LikelyPathogenic/ Pathogenic multiple submissions. The variant affects the GT donor splice site downstream of exon 2. This variant is predicted to cause loss of normal protein function through protein truncation. Loss of function variants have been previouslyreported to be disease causing. For these reasons, this variant has been classified as Pathogenic. - |
Pathogenic, criteria provided, single submitter | clinical testing | Mendelics | May 04, 2022 | - - |
Pathogenic, criteria provided, single submitter | clinical testing | Baylor Genetics | Feb 09, 2021 | This variant was determined to be pathogenic according to ACMG Guidelines, 2015 [PMID:25741868]. - |
Pathogenic, criteria provided, single submitter | clinical testing | Illumina Laboratory Services, Illumina | May 12, 2021 | The SBDS c.258+2T>C variant, also described as p.Cys84fsTer3, impacts the canonical splice donor site and results in an 8-bp deletion consistent with the use of a cryptic splice site and causing a frameshift and premature termination of the protein (Boocock et al. 2003). This variant, which occurs as a result of a gene conversion event with the nearby and highly homologous pseudogene SBDSP, is one of the most common disease-associated alleles in the SBDS gene (Nelson and Myers 2018). Across a small selection of the available literature, the c.258+2T>C variant was identified in 195 individuals with a confirmed or probable diagnosis of Shwachman-Diamond syndrome, including in a homozygous state in 13 individuals and in a compound heterozygous state in 182 individuals, 119 of whom carried the c.183_184delTAinsCT (p.Lys62Ter) variant, another common gene conversion variant, as the second variant (Boocock et al. 2003; Woloszynek et al. 2004; Myers et al. 2014; Cho et al. 2015; Ipatova et al. 2019). The c.258+2T>C variant was absent from 148 control individuals (Boocock et al. 2003; Woloszynek et al. 2004) but is reported at a frequency of 0.009412 in the European (Finnish) population of the Genome Aggregation Database (version 2.1.1). This population also includes two individuals who appear to be homozygous for this variant, though there are no homozygous individuals reported in a more recent version of the database (version 3.1.1). The presence of the SBDSP pseudogene may complicate the accurate reporting of the variant frequency in the population (Nelson and Myers 2018). In a functional study, Orelio et al. (2011) transiently transfected HeLa cells with GFP constructs containing full length or truncated protein due to the c.258+2T>C variant. The authors observed that the full-length protein was localized in both the nucleus and cytoplasm, while the truncated protein was mainly detected in the nucleus. The presence of the variant also affected nuclear import of SBDS proteins. Based on the available evidence, the c.258+2T>C variant is classified as pathogenic for Shwachman-Diamond syndrome. - |
Likely pathogenic, criteria provided, single submitter | clinical testing | Bioinformatics Unit, Institut Pasteur de Montevideo | May 03, 2022 | - - |
Pathogenic, criteria provided, single submitter | clinical testing | Genomic Diagnostic Laboratory, Division of Genomic Diagnostics, Children's Hospital of Philadelphia | Dec 16, 2021 | - - |
Pathogenic, criteria provided, single submitter | clinical testing | Laboratorio de Genetica e Diagnostico Molecular, Hospital Israelita Albert Einstein | Apr 07, 2022 | ACMG classification criteria: PVS1 strong, PS3 supporting, PM3 very strong - |
Pathogenic, criteria provided, single submitter | clinical testing | Revvity Omics, Revvity | Nov 07, 2023 | - - |
Pathogenic, criteria provided, single submitter | clinical testing | Centogene AG - the Rare Disease Company | Nov 05, 2021 | - - |
Pathogenic, criteria provided, single submitter | clinical testing | Baylor Genetics | May 27, 2020 | This variant was determined to be pathogenic according to ACMG Guidelines, 2015 [PMID:25741868]. - |
Pathogenic, criteria provided, single submitter | clinical testing | Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center | May 18, 2016 | - - |
Pathogenic, no assertion criteria provided | clinical testing | Genetic Services Laboratory, University of Chicago | Jan 10, 2022 | This pathogenic sequence change has previously been described in individuals with Shwachman- Diamond syndrome in the homozygous or compound heterozygous state with other pathogenic changes (PMIDs 12496757, 27127007, 21695142,15284109, 15942154). This sequence change was also identified in 4 individuals in the heterozygous state with apparently acquired aplastic anemia and short telomeres in granulocytes (PMID: 17478638); however further studies with larger populations are required to establish the association. Functional studies have shown that this sequence change results in a non-expressed product and impairs SBDS function (PMID 17478638). These collective evidences indicate that this sequence change is pathogenic. - |
not provided, no classification provided | literature only | GeneReviews | - | - - |
Pathogenic, criteria provided, single submitter | clinical testing | Rady Children's Institute for Genomic Medicine, Rady Children's Hospital San Diego | Jul 10, 2018 | The c.258+2T>C variant is a canonical splice donor variant in the SBDS gene. The variant is one of the most common pathogenic variants in SBDS (PMID: 20301722), and has been reported by multiple laboratories in the ClinVar as pathogenic (variant ID: 3196). Functional studies suggest that the c.258+2 T>C variant affects the protein's cellular localization and motility (PMID: 21695142). The c.258+2T>C variant is present in ExAC at 0.39% (474/120486), but it is not present in the homozygous state. Based on the combined evidence, the variant is classified as pathogenic. - |