19-7642116-G-T

Variant names:

• chr19-7642116-G-T
• NM_006949.4:c.661G>T

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_006949.4(STXBP2):​c.661G>T​(p.Glu221*) variant causes a stop gained, splice region change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: STXBP2 NM_006949.4 stop_gained, splice_region
• Scores: Splicing: ADA: 0.7161
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 6.46

Genes affected

STXBP2 (HGNC:11445): (syntaxin binding protein 2) This gene encodes a member of the STXBP/unc-18/SEC1 family. The encoded protein is involved in intracellular trafficking, control of SNARE (soluble NSF attachment protein receptor) complex assembly, and the release of cytotoxic granules by natural killer cells. Mutations in this gene are associated with familial hemophagocytic lymphohistiocytosis. Alternatively spliced transcript variants encoding different isoforms have been noted for this gene. [provided by RefSeq, Jan 2013]

ENSG00000268400 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 19-7642116-G-T is Pathogenic according to our data. Variant chr19-7642116-G-T is described in ClinVar as [Pathogenic]. Clinvar id is 2752778.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
STXBP2	NM_006949.4	c.661G>T	p.Glu221*	stop_gained, splice_region_variant	Exon 8 of 19	ENST00000221283.10	NP_008880.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
STXBP2	ENST00000221283.10	c.661G>T	p.Glu221*	stop_gained, splice_region_variant	Exon 8 of 19	1	NM_006949.4	ENSP00000221283.4
ENSG00000268400	ENST00000698368.1	n.*764G>T		splice_region_variant, non_coding_transcript_exon_variant	Exon 10 of 20			ENSP00000513686.1
ENSG00000268400	ENST00000698368.1	n.*764G>T		3_prime_UTR_variant	Exon 10 of 20			ENSP00000513686.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 35

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Familial hemophagocytic lymphohistiocytosis 5 Pathogenic:1

Aug 16, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Glu221*) in the STXBP2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in STXBP2 are known to be pathogenic (PMID: 19804848, 22451424). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with STXBP2-related conditions. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.62	D
BayesDel_noAF	Pathogenic	0.55
CADD	Pathogenic	50
DANN	Uncertain	1.0
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.84
FATHMM_MKL	Pathogenic	0.97	D
Vest4		0.89, 0.89
GERP RS		4.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.72
dbscSNV1_RF	Pathogenic	0.80
SpliceAI score (max)		0.010		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: chr19-7707002;