chr19-7642116-G-A

Variant summary

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

The NM_006949.4(STXBP2):​c.661G>A​(p.Glu221Lys) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.000168 in 1,614,096 control chromosomes in the GnomAD database, including 1 homozygotes. 2/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.00012 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00017 ( 1 hom. )

Consequence

STXBP2
NM_006949.4 missense, splice_region

Scores

1
13
5
Splicing: ADA: 0.6049
1
1

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 6.46
Variant links:
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]

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ACMG classification

Classification made for transcript

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 Protein UniProt
STXBP2NM_006949.4 linkuse as main transcriptc.661G>A p.Glu221Lys missense_variant, splice_region_variant 8/19 ENST00000221283.10 NP_008880.2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
STXBP2ENST00000221283.10 linkuse as main transcriptc.661G>A p.Glu221Lys missense_variant, splice_region_variant 8/191 NM_006949.4 ENSP00000221283 P4Q15833-1

Frequencies

GnomAD3 genomes
AF:
0.000125
AC:
19
AN:
152160
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000483
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
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:
0.000191
Gnomad OTH
AF:
0.000958
GnomAD3 exomes
AF:
0.000139
AC:
35
AN:
250952
Hom.:
1
AF XY:
0.000147
AC XY:
20
AN XY:
135764
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000521
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000141
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.000172
AC:
252
AN:
1461824
Hom.:
1
Cov.:
35
AF XY:
0.000161
AC XY:
117
AN XY:
727212
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.000425
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.0000187
Gnomad4 NFE exome
AF:
0.000198
Gnomad4 OTH exome
AF:
0.000182
GnomAD4 genome
AF:
0.000125
AC:
19
AN:
152272
Hom.:
0
Cov.:
32
AF XY:
0.000134
AC XY:
10
AN XY:
74442
show subpopulations
Gnomad4 AFR
AF:
0.0000481
Gnomad4 AMR
AF:
0.000131
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.000191
Gnomad4 OTH
AF:
0.000948
Alfa
AF:
0.000240
Hom.:
0
Bravo
AF:
0.000159
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000778
AC:
3
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000824
AC:
10
EpiCase
AF:
0.000327
EpiControl
AF:
0.000237

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Inborn genetic diseases Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsAug 29, 2022The c.661G>A (p.E221K) alteration is located in exon 8 (coding exon 8) of the STXBP2 gene. This alteration results from a G to A substitution at nucleotide position 661, causing the glutamic acid (E) at amino acid position 221 to be replaced by a lysine (K). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -
Familial hemophagocytic lymphohistiocytosis 5 Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpNov 01, 2022This sequence change replaces glutamic acid, which is acidic and polar, with lysine, which is basic and polar, at codon 221 of the STXBP2 protein (p.Glu221Lys). This variant is present in population databases (rs201649843, gnomAD 0.05%), including at least one homozygous and/or hemizygous individual. This variant has not been reported in the literature in individuals affected with STXBP2-related conditions. ClinVar contains an entry for this variant (Variation ID: 567849). 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: "Deleterious"; PolyPhen-2: "Possibly 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. -
not provided Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingGeneDxApr 04, 2022In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.35
BayesDel_addAF
Benign
-0.064
T
BayesDel_noAF
Uncertain
0.020
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Benign
0.41
.;.;T;.
Eigen
Uncertain
0.59
Eigen_PC
Uncertain
0.57
FATHMM_MKL
Uncertain
0.92
D
LIST_S2
Uncertain
0.94
D;D;D;D
M_CAP
Uncertain
0.13
D
MetaRNN
Uncertain
0.58
D;T;T;T
MetaSVM
Uncertain
0.0065
D
MutationAssessor
Benign
2.0
.;.;M;.
MutationTaster
Benign
1.0
D;D;D
PrimateAI
Uncertain
0.65
T
PROVEAN
Uncertain
-2.8
.;D;D;D
REVEL
Uncertain
0.61
Sift
Benign
0.24
.;T;T;T
Sift4G
Uncertain
0.0050
D;T;T;T
Polyphen
1.0
.;.;D;D
Vest4
0.78, 0.78, 0.79
MVP
0.86
MPC
0.84
ClinPred
0.48
T
GERP RS
4.4
Varity_R
0.67
gMVP
0.61

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.60
dbscSNV1_RF
Pathogenic
0.77
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

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs201649843; hg19: chr19-7707002; API