rs200963884

Variant names:

• chr5-149980292-G-C
• rs200963884
• NM_000112.4:c.700-1G>C

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000112.4(SLC26A2):​c.700-1G>C variant causes a splice acceptor, intron change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000682 in 1,612,766 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: 𝑓 0.000046 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: SLC26A2 NM_000112.4 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:6
• Conservation: PhyloP100: 10.0

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 18 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 8.1, offset of 4, new splice context is: atatccttccttccacgtAGcga. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 5-149980292-G-C is Pathogenic according to our data. Variant chr5-149980292-G-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 56027.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr5-149980292-G-C is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SLC26A2	NM_000112.4	c.700-1G>C		splice_acceptor_variant, intron_variant	Intron 2 of 2	ENST00000286298.5	NP_000103.2
SLC26A2	XM_017009191.3	c.700-1G>C		splice_acceptor_variant, intron_variant	Intron 2 of 3		XP_016864680.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SLC26A2	ENST00000286298.5	c.700-1G>C		splice_acceptor_variant, intron_variant	Intron 2 of 2	1	NM_000112.4	ENSP00000286298.4
SLC26A2	ENST00000503336.1	c.372+1941G>C		intron_variant	Intron 1 of 1	3		ENSP00000426053.1

Frequencies

GnomAD3 genomes AF: 0.0000460 AC: 7 AN: 152192 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000458

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1460574 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 726736

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000447

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: 0.0000331

GnomAD4 genome AF: 0.0000460 AC: 7 AN: 152192 Hom.: 0 Cov.: 32 AF XY: 0.0000403 AC XY: 3 AN XY: 74358

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.000458

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000982

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:6

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:2

Nov 11, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects an acceptor splice site in intron 2 of the SLC26A2 gene. While this variant is not anticipated to result in nonsense mediated decay, it likely alters RNA splicing and results in a disrupted protein product. This variant is not present in population databases (gnomAD no frequency). Disruption of this splice site has been observed in individual(s) with diastrophic dysplasia (PMID: 7923357, 21155763; internal data). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. This variant is also known as c.727-1G>C. ClinVar contains an entry for this variant (Variation ID: 56027). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Oct 28, 2021

Fulgent Genetics, Fulgent Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Multiple epiphyseal dysplasia type 4 Pathogenic:1

Jun 13, 2014

Counsyl

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: literature only

- -

Achondrogenesis, type IB Pathogenic:1

Mar 26, 2024

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Diastrophic dysplasia Pathogenic:1

-

Juha Muilu Group; Institute for Molecular Medicine Finland (FIMM)

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Osteochondrodysplasia Pathogenic:1

Nov 13, 2024

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

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: SLC26A2 c.700-1G>C (also described as c.727-1G>C in the literature) is located in the canonical splice-site of the last intron and is predicted to affect mRNA splicing resulting in a significantly altered protein due to either exon skipping, shortening, or inclusion of intronic material. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing and loss of SLC26A2 function. Several computational tools predict a significant impact on normal splicing: Four predict the variant abolishes a 3 acceptor site. Four predict the variant creates a 3 acceptor site. However, these predictions have yet to be confirmed by functional studies. The variant was absent in 251216 control chromosomes (gnomAD). c.700-1G>C has been reported in the literature in individuals affected with sulfate transporter-related osteochondrodysplasia (examples: Barbosa_2011, Hastbacka_1994, Silveira_2022). These data indicate that the variant is likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 21155763, 11241838, 7923357, 34064542, 36660027). ClinVar contains an entry for this variant (Variation ID: 56027). Based on the evidence outlined above, the variant was classified as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.16
CADD	Pathogenic	32
DANN	Uncertain	1.0
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Pathogenic	1.0	D
GERP RS		5.3

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		0.82		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.82		Position offset: 1

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

Publications

LitVar

Other links and lift over

dbSNP: rs200963884; hg19: chr5-149359855;