7-66991194-CT-C

Position:

• chr7-66991194-CT-C

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PVS1_Strong PM2 PP5_Moderate

The NM_016038.4(SBDS):​c.566delA​(p.Lys189fs) variant causes a frameshift change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Likely pathogenic (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: SBDS NM_016038.4 frameshift
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 5.39

Genes affected

SBDS (HGNC:19440): (SBDS ribosome maturation factor) This gene encodes a highly conserved protein that plays an essential role in ribosome biogenesis. The encoded protein interacts with elongation factor-like GTPase 1 to disassociate eukaryotic initiation factor 6 from the late cytoplasmic pre-60S ribosomal subunit allowing assembly of the 80S subunit. Mutations within this gene are associated with the autosomal recessive disorder Shwachman-Bodian-Diamond syndrome. This gene has a closely linked pseudogene that is distally located. [provided by RefSeq, Jan 2017]

SBDS (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most 50 bp of the penultimate exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.248 CDS is truncated, and there are 1 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 7-66991194-CT-C is Pathogenic according to our data. Variant chr7-66991194-CT-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 3377150.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SBDS	NM_016038.4	c.566delA	p.Lys189fs	frameshift_variant	4/5	ENST00000246868.7	NP_057122.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SBDS	ENST00000246868.7	c.566delA	p.Lys189fs	frameshift_variant	4/5	1	NM_016038.4	ENSP00000246868.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Shwachman-Diamond syndrome 1 Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Oct 09, 2024

Based on the classification scheme VCGS_Germline_v1.3.5, this variant is classified as Likely 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) 0205 - Variant is predicted to result in a truncated protein (premature termination codon is NOT located at least 54 nucleotides upstream of the final exon-exon junction) with less than 1/3 of the protein sequence affected. (SP) 0251 - This variant is heterozygous. (I) 0301 - Variant is absent from gnomAD (v2, v3 and v4). (SP) 0600 - Variant affects the annotated SBDS C-terminal domain (DECIPHER). (I) 0702 - Other downstream protein truncating variants comparable to the one identified in this case have strong previous evidence for pathogenicity (ClinVar). (SP) 0807 - This variant has no previous evidence of pathogenicity. (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.090		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr7-66456181;