19-7637156-C-T

Position:

• chr19-7637156-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_006949.4(STXBP2):​c.7C>T​(p.Pro3Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000918 in 1,089,402 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. P3P) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000092 (0 hom.)
• Consequence: STXBP2 NM_006949.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.72

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
STXBP2	NM_006949.4	c.7C>T	p.Pro3Ser	missense_variant	1/19	ENST00000221283.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
STXBP2	ENST00000221283.10	c.7C>T	p.Pro3Ser	missense_variant	1/19	1	NM_006949.4	P4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000918 AC: 10 AN: 1089402 Hom.: 0 Cov.: 31 AF XY: 0.00000972 AC XY: 5 AN XY: 514638

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: 0.00

Gnomad4 NFE exome AF: 0.00000869

Gnomad4 OTH exome AF: 0.0000457

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

Asia WGS AF: 0.000289 AC: 1 AN: 3476

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Familial hemophagocytic lymphohistiocytosis 5 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 13, 2022

This sequence change replaces proline, which is neutral and non-polar, with serine, which is neutral and polar, at codon 3 of the STXBP2 protein (p.Pro3Ser). 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. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.14
BayesDel_addAF	Benign	-0.023	T
BayesDel_noAF	Benign	-0.27
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Benign	0.039	.;.;T;.
Eigen	Benign	0.13
Eigen_PC	Benign	0.21
FATHMM_MKL	Uncertain	0.77	D
LIST_S2	Uncertain	0.94	D;D;D;D
M_CAP	Pathogenic	0.62	D
MetaRNN	Uncertain	0.46	T;T;T;T
MetaSVM	Benign	-0.50	T
MutationAssessor	Uncertain	2.1	.;M;M;M
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.76	T
PROVEAN	Benign	-1.2	.;N;N;N
REVEL	Benign	0.19
Sift	Benign	0.047	.;D;D;D
Sift4G	Benign	0.10	T;T;T;T
Polyphen		0.70, 0.80	.;.;P;P
Vest4		0.12, 0.12, 0.13
MutPred		0.39		Gain of MoRF binding (P = 0.0331);Gain of MoRF binding (P = 0.0331);Gain of MoRF binding (P = 0.0331);Gain of MoRF binding (P = 0.0331);
MVP		0.85
MPC		0.89
ClinPred		0.95	D
GERP RS		4.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.6
Varity_R		0.19
gMVP		0.33

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

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

Publications

LitVar

Other links and lift over

dbSNP: rs1015212727; hg19: chr19-7702042;