X-47572956-C-A

Variant names:

• chrX-47572956-C-A
• NM_006950.3:c.2026G>T

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_006950.3(SYN1):​c.2026G>T​(p.Ala676Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 11/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 22)
• Consequence: SYN1 NM_006950.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.802

Genes affected

SYN1 (HGNC:11494): (synapsin I) This gene is a member of the synapsin gene family. Synapsins encode neuronal phosphoproteins which associate with the cytoplasmic surface of synaptic vesicles. Family members are characterized by common protein domains, and they are implicated in synaptogenesis and the modulation of neurotransmitter release, suggesting a potential role in several neuropsychiatric diseases. This member of the synapsin family plays a role in regulation of axonogenesis and synaptogenesis. The protein encoded serves as a substrate for several different protein kinases and phosphorylation may function in the regulation of this protein in the nerve terminal. Mutations in this gene may be associated with X-linked disorders with primary neuronal degeneration such as Rett syndrome. Alternatively spliced transcript variants encoding different isoforms have been identified. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.11711544).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SYN1	NM_006950.3	c.2026G>T	p.Ala676Ser	missense_variant	Exon 13 of 13	ENST00000295987.13	NP_008881.2
SYN1	NM_133499.2	c.1988G>T	p.Ser663Ile	missense_variant	Exon 13 of 13		NP_598006.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SYN1	ENST00000295987.13	c.2026G>T	p.Ala676Ser	missense_variant	Exon 13 of 13	2	NM_006950.3	ENSP00000295987.7
SYN1	ENST00000340666.5	c.1988G>T	p.Ser663Ile	missense_variant	Exon 13 of 13	1		ENSP00000343206.4
SYN1	ENST00000640721.1	c.76G>T	p.Ala26Ser	missense_variant	Exon 2 of 2	5		ENSP00000492857.1

Frequencies

GnomAD3 genomes Cov.: 22

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 22

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Epilepsy, X-linked 1, with variable learning disabilities and behavior disorders Uncertain:1

Dec 04, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces serine, which is neutral and polar, with isoleucine, which is neutral and non-polar, at codon 663 of the SYN1 protein (p.Ser663Ile). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with SYN1-related conditions. Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. 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	0.080
BayesDel_addAF	Benign	-0.41	T
BayesDel_noAF	Benign	-0.83
CADD	Benign	20
DANN	Uncertain	0.99
DEOGEN2	Benign	0.13	T;.
FATHMM_MKL	Benign	0.46	N
LIST_S2	Benign	0.73	T;T
M_CAP	Benign	0.0096	T
MetaRNN	Benign	0.12	T;T
MetaSVM	Benign	-1.0	T
PrimateAI	Uncertain	0.50	T
PROVEAN	Benign	0.22	N;.
REVEL	Benign	0.056
Sift	Benign	1.0	T;.
Sift4G	Benign	1.0	T;.
Polyphen		0.14	B;.
Vest4		0.11
MutPred		0.27		Gain of phosphorylation at A676 (P = 0.0056);.;
MVP		0.41
MPC		1.7
ClinPred		0.63	D
GERP RS		4.8
Varity_R		0.15
gMVP		0.33

Splicing

Name	Calibrated prediction	Score	Prediction
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: chrX-47432355;