rs1554095433

chr5-149981713-T-TTC

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PVS1_Strong PM2 PP5_Very_Strong

The NM_000112.4(SLC26A2):c.2124_2125dup(p.Phe709SerfsTer27) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,458,984 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: SLC26A2 NM_000112.4 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: -0.258

Genes affected

SLC26A2 (HGNC:10994): (solute carrier family 26 member 2) The diastrophic dysplasia sulfate transporter is a transmembrane glycoprotein implicated in the pathogenesis of several human chondrodysplasias. It apparently is critical in cartilage for sulfation of proteoglycans and matrix organization. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Pathogenic. Variant got 14 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 4 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 5-149981713-T-TTC is Pathogenic according to our data. Variant chr5-149981713-T-TTC is described in ClinVar as [Likely_pathogenic]. Clinvar id is 436750.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SLC26A2	NM_000112.4	c.2124_2125dup	p.Phe709SerfsTer27	frameshift_variant	3/3	ENST00000286298.5
SLC26A2	XM_017009191.3	c.2124_2125dup	p.Phe709SerfsTer27	frameshift_variant	3/4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SLC26A2	ENST00000286298.5	c.2124_2125dup	p.Phe709SerfsTer27	frameshift_variant	3/3	1	NM_000112.4	P1
SLC26A2	ENST00000503336.1	c.372+3366_372+3367dup		intron_variant		3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000806 AC: 2 AN: 248236 Hom.: 0 AF XY: 0.00000745 AC XY: 1 AN XY: 134260

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000589

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1458984 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 725834

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000453

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Diastrophic dysplasia;C0265274:Achondrogenesis, type IB;C1847593:Multiple epiphyseal dysplasia type 4;C1850554:Atelosteogenesis type II Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Dec 30, 2023

This sequence change creates a premature translational stop signal (p.Phe709Serfs*27) in the SLC26A2 gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 31 amino acid(s) of the SLC26A2 protein. This variant is present in population databases (no rsID available, gnomAD 0.006%). This variant has not been reported in the literature in individuals affected with SLC26A2-related conditions. ClinVar contains an entry for this variant (Variation ID: 436750). This variant disrupts a region of the SLC26A2 protein in which other variant(s) (p.Ala715Val) have been determined to be pathogenic (PMID: 8571951, 11448940, 15294877, 21077204, 21922596). This suggests that this is a clinically significant region of the protein, and that variants that disrupt it are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

not provided Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Genetic Services Laboratory, University of Chicago

Jun 16, 2016

- -

Sulfate transporter-related osteochondrodysplasia Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Oct 12, 2021

Variant summary: SLC26A2 c.2124_2125dupCT (p.Phe709SerfsX27) results in a premature termination codon, predicted to cause a truncation of the encoded protein. This premature termination is positioned 3 codons away from the last amino acid in the protein (i.e. aa 739). A different variant causing premature termination at the same codon as this variant (i.e. c.2119_2120dupCT, p.Leu708PhefsX28) has been reported in a patient affected with diastrophic dysplasia (PMID: 11241838). The variant allele was found at a frequency of 8.1e-06 in 248236 control chromosomes (gnomAD). To our knowledge, no occurrence of c.2124_2125dupCT in individuals affected with Sulfate Transporter-Related Osteochondrodysplasia and no experimental evidence demonstrating its impact on protein function have been reported. A ClinVar submitter (evaluation after 2014) cites the variant as likely pathogenic. Based on the evidence outlined above, the variant was classified as likely pathogenic. -

Computational scores

Source: dbNSFP v4.3

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs1554095433; hg19: chr5-149361276;