4-89786796-T-G

Variant names:

• chr4-89786796-T-G
• rs2737033
• NM_000345.4:c.306+35450A>C

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_000345.4(SNCA):​c.306+35450A>C variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000264 in 151,722 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: 𝑓 0.000026 (0 hom., cov: 31)
• Consequence: SNCA NM_000345.4 intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -2.81
• Publications: 12 publications found

Genes affected

SNCA (HGNC:11138): (synuclein alpha) Alpha-synuclein is a member of the synuclein family, which also includes beta- and gamma-synuclein. Synucleins are abundantly expressed in the brain and alpha- and beta-synuclein inhibit phospholipase D2 selectively. SNCA may serve to integrate presynaptic signaling and membrane trafficking. Defects in SNCA have been implicated in the pathogenesis of Parkinson disease. SNCA peptides are a major component of amyloid plaques in the brains of patients with Alzheimer's disease. Alternatively spliced transcripts encoding different isoforms have been identified for this gene. [provided by RefSeq, Feb 2016]

SNCA Gene-Disease associations (from GenCC):

• autosomal dominant Parkinson disease 4

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• Parkinson disease

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen, Ambry Genetics
• autosomal dominant Parkinson disease 1

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
• Lewy body dementia

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• hereditary late onset Parkinson disease

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• parkinsonian-pyramidal syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.91).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SNCA	NM_000345.4	c.306+35450A>C		intron_variant	Intron 4 of 5	ENST00000394991.8	NP_000336.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SNCA	ENST00000394991.8	c.306+35450A>C		intron_variant	Intron 4 of 5	1	NM_000345.4	ENSP00000378442.4

Frequencies

GnomAD3 genomes AF: 0.0000264 AC: 4 AN: 151722 Hom.: 0 Cov.: 31

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000132

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: 0.0000294

Gnomad OTH AF: 0.00

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome AF: 0.0000264 AC: 4 AN: 151722 Hom.: 0 Cov.: 31 AF XY: 0.0000405 AC XY: 3 AN XY: 74046

African (AFR) AF: 0.00 AC: 0 AN: 41344

American (AMR) AF: 0.000132 AC: 2 AN: 15196

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.00 AC: 0 AN: 5164

South Asian (SAS) AF: 0.00 AC: 0 AN: 4808

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10514

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000294 AC: 2 AN: 67916

Other (OTH) AF: 0.00 AC: 0 AN: 2084

Alfa AF: 0.00 Hom.: 423

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.91
CADD	Benign	0.034
DANN	Benign	0.70
PhyloP100		-2.8

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

Other links and lift over

dbSNP: rs2737033; hg19: chr4-90707947;