rs1553691139

Variant names:

• chr3-11031279-GGTGA-G
• rs1553691139
• NM_003042.4:c.1426+3_1426+6delGAGT

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_003042.4(SLC6A1):​c.1426+3_1426+6delGAGT variant causes a splice region, intron change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 1/1 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: SLC6A1 NM_003042.4 splice_region, intron
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.83
• Publications: 0 publications found

Genes affected

SLC6A1 (HGNC:11042): (solute carrier family 6 member 1) The protein encoded by this gene is a gamma-aminobutyric acid (GABA) transporter that localizes to the plasma membrane. The encoded protein removes GABA from the synaptic cleft, restoring it to presynaptic terminals. [provided by RefSeq, Jan 2017]

SLC6A1 Gene-Disease associations (from GenCC):

• epilepsy with myoclonic atonic seizures

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Illumina, G2P, Labcorp Genetics (formerly Invitae)
• myoclonic-astatic epilepsy

  Inheritance: Unknown Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SLC6A1	NM_003042.4	c.1426+3_1426+6delGAGT		splice_region_variant, intron_variant	Intron 13 of 15	ENST00000287766.10	NP_003033.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SLC6A1	ENST00000287766.10	c.1426+1_1426+4delGTGA		splice_donor_variant, splice_region_variant, intron_variant	Intron 13 of 15	1	NM_003042.4	ENSP00000287766.4

Frequencies

GnomAD3 genomes Cov.: 32

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Epilepsy with myoclonic atonic seizures Uncertain:1

Apr 25, 2017

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In summary, this is a novel intronic change with uncertain impact on splicing. It has been classified as a Variant of Uncertain Significance. Nucleotide substitutions within the consensus splice site are relatively common causes of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of nucleotide changes on RNA splicing suggest that this variant may alter RNA splicing, but this prediction has not been confirmed by published transcriptional studies. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a SLC6A1-related disease. This sequence change falls in intron 13 of the SLC6A1 gene. It does not directly change the encoded amino acid sequence of the SLC6A1 protein, but it does affect nucleotides within the consensus splice site of the intron. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		9.8

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.73		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.73		Position offset: 0

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

Other links and lift over

dbSNP: rs1553691139; hg19: chr3-11072965;