rs386833486

Positions:

• chr7-107789690-T-C

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1_Moderate PM2 PP5_Very_Strong

The NM_000111.3(SLC26A3):​c.571-2A>G variant causes a splice acceptor change. The variant allele was found at a frequency of 0.0000705 in 1,460,392 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: not found (cov: 31)
  • Exomes 𝑓: 0.000071 (0 hom.)
• Consequence: SLC26A3 NM_000111.3 splice_acceptor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 5.76

Genes affected

SLC26A3 (HGNC:3018): (solute carrier family 26 member 3) The protein encoded by this gene is a transmembrane glycoprotein that transports chloride ions across the cell membrane in exchange for bicarbonate ions. It is localized to the mucosa of the lower intestinal tract, particularly to the apical membrane of columnar epithelium and some goblet cells. The protein is essential for intestinal chloride absorption, and mutations in this gene have been associated with congenital chloride diarrhea. [provided by RefSeq, Oct 2008]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.071459696 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 7-107789690-T-C is Pathogenic according to our data. Variant chr7-107789690-T-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 56005.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr7-107789690-T-C is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SLC26A3	NM_000111.3	c.571-2A>G		splice_acceptor_variant		ENST00000340010.10	NP_000102.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SLC26A3	ENST00000340010.10	c.571-2A>G		splice_acceptor_variant		1	NM_000111.3	ENSP00000345873	P1
SLC26A3	ENST00000379083.7	c.*362-2A>G		splice_acceptor_variant, NMD_transcript_variant		2		ENSP00000368375

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD3 exomes AF: 0.0000323 AC: 8 AN: 247820 Hom.: 0 AF XY: 0.0000299 AC XY: 4 AN XY: 133882

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.0000931

Gnomad NFE exome AF: 0.0000447

Gnomad OTH exome AF: 0.000165

GnomAD4 exome AF: 0.0000705 AC: 103 AN: 1460392 Hom.: 0 Cov.: 32 AF XY: 0.0000757 AC XY: 55 AN XY: 726286

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.0000750

Gnomad4 NFE exome AF: 0.0000882

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 31

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:2

Likely pathogenic, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	May 01, 2016	- -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 21, 2024	This sequence change affects an acceptor splice site in intron 5 of the SLC26A3 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in SLC26A3 are known to be pathogenic (PMID: 9718329, 21394828). This variant is present in population databases (rs386833486, gnomAD 0.009%). Disruption of this splice site has been observed in individual(s) with congenital chloride diarrhea (PMID: 9718329). This variant is also known as IVS5-2A>G. ClinVar contains an entry for this variant (Variation ID: 56005). 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. -

Congenital secretory diarrhea, chloride type Pathogenic:1

Likely pathogenic, no assertion criteria provided

literature only

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

-

- -

SLC26A3-related disorder Pathogenic:1

Likely pathogenic, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Dec 16, 2023

The SLC26A3 c.571-2A>G variant is predicted to disrupt the AG splice acceptor site and interfere with normal splicing. This variant has been reported along with a second SLC26A3 variant in an individual with congenital chloride diarrhea (Table 1 and 2, referred to as IVS5-2A>G, Hoglund et al. 1998. PubMed ID: 9718329). This variant is reported in 0.0093% of alleles in individuals of European (Finnish) descent in gnomAD. Variants that disrupt the consensus splice acceptor site in SLC26A3 are expected to be pathogenic. This variant is interpreted as likely pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.53	D
BayesDel_noAF	Uncertain	0.030
CADD	Pathogenic	33
DANN	Uncertain	0.99
Eigen	Pathogenic	0.97
Eigen_PC	Pathogenic	0.77
FATHMM_MKL	Pathogenic	1.0	D
MutationTaster	Benign	1.0	D;D
GERP RS		5.5

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.89
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.74		Position offset: -36
DS_AL_spliceai		1.0		Position offset: -2

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

Publications

LitVar

Other links and lift over

dbSNP: rs386833486; hg19: chr7-107430135;