chr5-176629600-C-T

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BS2

The NM_003085.5(SNCB):​c.55G>A​(p.Ala19Thr) variant causes a missense change. The variant allele was found at a frequency of 0.00000372 in 1,613,568 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

SNCB
NM_003085.5 missense

Scores

5
13
1

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 6.14
Variant links:
Genes affected
SNCB (HGNC:11140): (synuclein beta) This gene encodes a member of a small family of proteins that inhibit phospholipase D2 and may function in neuronal plasticity. The encoded protein is abundant in lesions of patients with Alzheimer disease. A mutation in this gene was found in individuals with dementia with Lewy bodies. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Dec 2015]
MIR4281 (HGNC:38357): (microRNA 4281) microRNAs (miRNAs) are short (20-24 nt) non-coding RNAs that are involved in post-transcriptional regulation of gene expression in multicellular organisms by affecting both the stability and translation of mRNAs. miRNAs are transcribed by RNA polymerase II as part of capped and polyadenylated primary transcripts (pri-miRNAs) that can be either protein-coding or non-coding. The primary transcript is cleaved by the Drosha ribonuclease III enzyme to produce an approximately 70-nt stem-loop precursor miRNA (pre-miRNA), which is further cleaved by the cytoplasmic Dicer ribonuclease to generate the mature miRNA and antisense miRNA star (miRNA*) products. The mature miRNA is incorporated into a RNA-induced silencing complex (RISC), which recognizes target mRNAs through imperfect base pairing with the miRNA and most commonly results in translational inhibition or destabilization of the target mRNA. The RefSeq represents the predicted microRNA stem-loop. [provided by RefSeq, Sep 2009]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -4 ACMG points.

BS2
High AC in GnomAdExome4 at 5 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SNCBNM_003085.5 linkc.55G>A p.Ala19Thr missense_variant Exon 2 of 6 ENST00000393693.7 NP_003076.1 Q16143

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SNCBENST00000393693.7 linkc.55G>A p.Ala19Thr missense_variant Exon 2 of 6 1 NM_003085.5 ENSP00000377296.2 Q16143

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152174
Hom.:
0
Cov.:
32
show subpopulations
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:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.00000342
AC:
5
AN:
1461394
Hom.:
0
Cov.:
34
AF XY:
0.00000413
AC XY:
3
AN XY:
727008
show subpopulations
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:
0.0000232
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000180
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152174
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74318
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000564
Hom.:
0
Bravo
AF:
0.0000302

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Lewy body dementia Uncertain:1
May 20, 2023
Neuberg Centre For Genomic Medicine, NCGM
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The observed missense variant c.55G>A(p.Ala19Thr) in SNCB gene has not been reported previously as a pathogenic variant nor as a benign variant, to our knowledge. The c.55G>A variant is reported with 0 frequency in gnomAD Exomes. The amino acid Alanine at position 19 is changed to a Threonine changing protein sequence and it might alter its composition and physico-chemical properties. Multiple lines of computational evidence (Polyphen-Probably damaging, SIFT-Damaging and Mutation Taster-Disease causing) predict a damaging effect on protein structure and function for this variant. The reference amino acid p.Ala19Thr in SNCB is predicted as conserved by GERP++ and PhyloP across 100 vertebrates. For these reasons, this variant has been classified as Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.78
BayesDel_addAF
Uncertain
0.15
D
BayesDel_noAF
Uncertain
-0.030
CADD
Pathogenic
29
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.88
D;D;D;D;D
Eigen
Uncertain
0.59
Eigen_PC
Uncertain
0.50
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Uncertain
0.97
.;D;.;.;D
M_CAP
Pathogenic
0.41
D
MetaRNN
Uncertain
0.72
D;D;D;D;D
MetaSVM
Uncertain
0.59
D
MutationAssessor
Uncertain
2.7
M;.;M;M;M
PrimateAI
Uncertain
0.68
T
PROVEAN
Uncertain
-2.6
D;.;D;D;D
REVEL
Pathogenic
0.77
Sift
Uncertain
0.0030
D;.;D;D;D
Sift4G
Uncertain
0.011
D;D;D;D;D
Polyphen
1.0
D;.;D;D;D
Vest4
0.48
MutPred
0.61
Gain of relative solvent accessibility (P = 0.0479);Gain of relative solvent accessibility (P = 0.0479);Gain of relative solvent accessibility (P = 0.0479);Gain of relative solvent accessibility (P = 0.0479);Gain of relative solvent accessibility (P = 0.0479);
MVP
0.93
MPC
1.4
ClinPred
0.98
D
GERP RS
3.4
Varity_R
0.59
gMVP
0.82

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

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

Other links and lift over

dbSNP: rs958646435; hg19: chr5-176056601; COSMIC: COSV59435792; COSMIC: COSV59435792; API