4-89724732-G-A

Variant names:

• chr4-89724732-G-A
• rs186189862
• NM_000345.4:c.*1896C>T

Variant summary

Our verdict is Benign. The variant received -16 ACMG points: 0P and 16B. BP4_Strong BP6_Very_Strong BS2

The NM_000345.4(SNCA):​c.*1896C>T variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00452 in 152,006 control chromosomes in the GnomAD database, including 7 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★).

• Frequency:
  • Genomes: 𝑓 0.0045 (7 hom., cov: 31)
  • Failed GnomAD Quality Control
• Consequence: SNCA NM_000345.4 3_prime_UTR
• Clinical Significance: Benign criteria provided, multiple submitters, no conflicts B:2
• Conservation: PhyloP100: -0.515
• Publications: 1 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

LOC124900602 (HGNC:):

ACMG classification

Our verdict: Benign. The variant received -16 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.9).
• BP6: Variant 4-89724732-G-A is Benign according to our data. Variant chr4-89724732-G-A is described in ClinVar as [Benign]. Clinvar id is 350066.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BS2: High Homozygotes in GnomAd4 at 7 AD,AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SNCA	NM_000345.4	c.*1896C>T		3_prime_UTR_variant	Exon 6 of 6	ENST00000394991.8	NP_000336.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SNCA	ENST00000394991.8	c.*1896C>T		3_prime_UTR_variant	Exon 6 of 6	1	NM_000345.4	ENSP00000378442.4

Frequencies

GnomAD3 genomes AF: 0.00451 AC: 685 AN: 151888 Hom.: 7 Cov.: 31

Gnomad AFR AF: 0.0157

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00125

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000415

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.0127

Gnomad NFE AF: 0.000103

Gnomad OTH AF: 0.00239

GnomAD4 exome Data not reliable, filtered out with message: AC0 AC: 0 AN: 0 Hom.: 0 Cov.: 0 AC XY: 0 AN XY: 0

African (AFR) AC: 0 AN: 0

American (AMR) AC: 0 AN: 0

Ashkenazi Jewish (ASJ) AC: 0 AN: 0

East Asian (EAS) AC: 0 AN: 0

South Asian (SAS) AC: 0 AN: 0

European-Finnish (FIN) AC: 0 AN: 0

Middle Eastern (MID) AC: 0 AN: 0

European-Non Finnish (NFE) AC: 0 AN: 0

Other (OTH) AC: 0 AN: 0

GnomAD4 genome AF: 0.00452 AC: 687 AN: 152006 Hom.: 7 Cov.: 31 AF XY: 0.00468 AC XY: 348 AN XY: 74298

African (AFR) AF: 0.0157 AC: 649 AN: 41460

American (AMR) AF: 0.00125 AC: 19 AN: 15254

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 5176

South Asian (SAS) AF: 0.000415 AC: 2 AN: 4816

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10562

Middle Eastern (MID) AF: 0.0171 AC: 5 AN: 292

European-Non Finnish (NFE) AF: 0.000103 AC: 7 AN: 67952

Other (OTH) AF: 0.00237 AC: 5 AN: 2114

Alfa AF: 0.00169 Hom.: 1

Bravo AF: 0.00523

Asia WGS AF: 0.00231 AC: 8 AN: 3478

ClinVar

Significance: Benign

Submissions summary: Benign:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Benign:1

-

Breakthrough Genomics, Breakthrough Genomics

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: not provided

- -

Parkinson Disease, Dominant Benign:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.90
CADD	Benign	0.81
DANN	Benign	0.34
PhyloP100		-0.52
Mutation Taster		=100/0	polymorphism

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: rs186189862; hg19: chr4-90645883; COSMIC: COSV104636273; COSMIC: COSV104636273;