chr17-55007566-C-T

Position:

• chr17-55007566-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 4P and 1B. PM1 PM2 BP4

The NM_178509.6(STXBP4):​c.635C>T​(p.Ser212Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000688 in 1,454,522 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: STXBP4 NM_178509.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.45

Genes affected

STXBP4 (HGNC:19694): (syntaxin binding protein 4) Enables syntaxin binding activity. Involved in several processes, including positive regulation of cell cycle G1/S phase transition; positive regulation of keratinocyte proliferation; and protein stabilization. Located in extracellular exosome. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM1: In a modified_residue Phosphoserine (size 0) in uniprot entity STXB4_HUMAN
• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.34055018).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
STXBP4	NM_178509.6	c.635C>T	p.Ser212Phe	missense_variant	8/18	ENST00000376352.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
STXBP4	ENST00000376352.6	c.635C>T	p.Ser212Phe	missense_variant	8/18	2	NM_178509.6	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.88e-7 AC: 1 AN: 1454522 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 723216

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: 9.01e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000468 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jun 22, 2023

The c.635C>T (p.S212F) alteration is located in exon 8 (coding exon 6) of the STXBP4 gene. This alteration results from a C to T substitution at nucleotide position 635, causing the serine (S) at amino acid position 212 to be replaced by a phenylalanine (F). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.15
BayesDel_addAF	Pathogenic	0.21	D
BayesDel_noAF	Uncertain	0.060
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Benign	0.074	T;T;T;.
Eigen	Pathogenic	0.76
Eigen_PC	Pathogenic	0.75
FATHMM_MKL	Uncertain	0.86	D
LIST_S2	Uncertain	0.91	D;D;D;D
M_CAP	Benign	0.013	T
MetaRNN	Benign	0.34	T;T;T;T
MetaSVM	Benign	-0.75	T
MutationAssessor	Uncertain	2.9	M;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Benign	0.43	T
PROVEAN	Benign	-2.1	N;N;N;D
REVEL	Uncertain	0.36
Sift	Benign	0.048	D;T;D;D
Sift4G	Benign	0.092	T;D;T;D
Polyphen		1.0	D;.;D;D
Vest4		0.27
MutPred		0.49		Gain of helix (P = 0.0425);Gain of helix (P = 0.0425);Gain of helix (P = 0.0425);.;
MVP		0.67
MPC		0.44
ClinPred		0.94	D
GERP RS		6.2
Varity_R		0.14
gMVP		0.51

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.17		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: rs2078032824; hg19: chr17-53084927;