1-216422148-T-G

Variant names:

• chr1-216422148-T-G
• rs752055316
• NM_206933.4:c.189A>C
• USH2A p.Arg63Arg

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_206933.4(USH2A):​c.189A>C​(p.Arg63Arg) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,622 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. Synonymous variant affecting the same amino acid position (i.e. R63R) has been classified as Likely benign. The gene USH2A is included in the ClinGen Criteria Specification Registry.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: USH2A NM_206933.4 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -1.13
• Publications: 0 publications found

Genes affected

USH2A (HGNC:12601): (usherin) This gene encodes a protein that contains laminin EGF motifs, a pentaxin domain, and many fibronectin type III motifs. The protein is found in the basement membrane, and may be important in development and homeostasis of the inner ear and retina. Mutations within this gene have been associated with Usher syndrome type IIa and retinitis pigmentosa. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Dec 2008]

USH2A Gene-Disease associations (from GenCC):

• Usher syndrome type 2A

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
• Usher syndrome type 2

  Inheritance: Unknown, AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• retinitis pigmentosa 39

  Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• retinitis pigmentosa

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Specifications for USH2A are available in the ClinGen Criteria Specification Registry and recommended for reference when assigning criteria.

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.87).
• BP7: Synonymous conserved (PhyloP=-1.13 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_206933.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	USH2A	NM_206933.4	MANE Select	c.189A>C	p.Arg63Arg	synonymous	Exon 2 of 72	NP_996816.3	O75445-1
	USH2A	NM_007123.6		c.189A>C	p.Arg63Arg	synonymous	Exon 2 of 21	NP_009054.6

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	USH2A	ENST00000307340.8	TSL:1 MANE Select	c.189A>C	p.Arg63Arg	synonymous	Exon 2 of 72	ENSP00000305941.3	O75445-1
	USH2A	ENST00000366942.3	TSL:1	c.189A>C	p.Arg63Arg	synonymous	Exon 2 of 21	ENSP00000355909.3	O75445-2
	USH2A	ENST00000674083.1		c.189A>C	p.Arg63Arg	synonymous	Exon 2 of 73	ENSP00000501296.1	O75445-3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 250972 AF XY: 0.00000737

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000881

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461622 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 727096

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33464

American (AMR) AF: 0.00 AC: 0 AN: 44674

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26118

East Asian (EAS) AF: 0.00 AC: 0 AN: 39692

South Asian (SAS) AF: 0.00 AC: 0 AN: 86252

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53400

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111884

Other (OTH) AF: 0.00 AC: 0 AN: 60372

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.87
CADD	Benign	0.65
DANN	Benign	0.57
PhyloP100		-1.1
Mutation Taster		=98/2	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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

dbSNP: rs752055316; hg19: chr1-216595490;