3-94015226-A-G

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_001001850.3(STX19):c.44T>C(p.Ile15Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000145 in 1,588,720 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000014 (0 hom.)
• Consequence: STX19 NM_001001850.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.986

Genes affected

STX19 (HGNC:19300): (syntaxin 19) Predicted to enable SNAP receptor activity and SNARE binding activity. Predicted to be involved in intracellular protein transport; synaptic vesicle fusion to presynaptic active zone membrane; and vesicle docking. Predicted to be part of SNARE complex. Predicted to be active in presynaptic active zone membrane and synaptic vesicle. Predicted to be integral component of membrane. [provided by Alliance of Genome Resources, Apr 2022]

ARL13B (HGNC:25419): (ADP ribosylation factor like GTPase 13B) This gene encodes a member of the ADP-ribosylation factor-like family. The encoded protein is a small GTPase that contains both N-terminal and C-terminal guanine nucleotide-binding motifs. This protein is localized in the cilia and plays a role in cilia formation and in maintenance of cilia. Mutations in this gene are the cause of Joubert syndrome 8. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Mar 2010]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.032608002).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
STX19	NM_001001850.3	c.44T>C	p.Ile15Thr	missense_variant	2/2	ENST00000315099.3
ARL13B	NM_001174150.2	c.380+11318A>G		intron_variant		ENST00000394222.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
STX19	ENST00000315099.3	c.44T>C	p.Ile15Thr	missense_variant	2/2	1	NM_001001850.3	P1
ARL13B	ENST00000394222.8	c.380+11318A>G		intron_variant		1	NM_001174150.2	P1

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152104 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000414

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000133 AC: 3 AN: 226300 Hom.: 0 AF XY: 0.0000245 AC XY: 3 AN XY: 122340

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000800

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000939

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000139 AC: 20 AN: 1436498 Hom.: 0 Cov.: 32 AF XY: 0.0000112 AC XY: 8 AN XY: 713280

Gnomad4 AFR exome AF: 0.0000314

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000506

Gnomad4 SAS exome AF: 0.0000620

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000996

Gnomad4 OTH exome AF: 0.0000169

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152222 Hom.: 0 Cov.: 33 AF XY: 0.0000269 AC XY: 2 AN XY: 74408

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000415

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000659 Hom.: 0

Bravo AF: 0.0000264

ExAC AF: 0.0000165 AC: 2

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

Jan 17, 2024

The c.44T>C (p.I15T) alteration is located in exon 2 (coding exon 1) of the STX19 gene. This alteration results from a T to C substitution at nucleotide position 44, causing the isoleucine (I) at amino acid position 15 to be replaced by a threonine (T). 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	0.061
BayesDel_addAF	Benign	-0.46	T
BayesDel_noAF	Benign	-0.70
Cadd	Benign	5.8
Dann	Benign	0.66
DEOGEN2	Benign	0.012	T
Eigen	Benign	-1.0
Eigen_PC	Benign	-0.91
FATHMM_MKL	Benign	0.12	N
LIST_S2	Benign	0.47	T
M_CAP	Benign	0.0044	T
MetaRNN	Benign	0.033	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.69	N
MutationTaster	Benign	1.0	N;N;N;N;N;N
PrimateAI	Benign	0.40	T
PROVEAN	Benign	-0.41	N
REVEL	Benign	0.014
Sift	Benign	0.20	T
Sift4G	Benign	0.40	T
Polyphen		0.0	B
Vest4		0.074
MVP		0.51
MPC		0.0088
ClinPred		0.023	T
GERP RS		1.6
Varity_R		0.032
gMVP		0.089

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: rs758588020; hg19: chr3-93734070;