8-86574433-C-A

Position:

• chr8-86574433-C-A

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_019098.5(CNGB3):​c.*1371G>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 0.00042 in 152,280 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.00042 (1 hom., cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: CNGB3 NM_019098.5 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:2
• Conservation: PhyloP100: -1.63

Genes affected

CNGB3 (HGNC:2153): (cyclic nucleotide gated channel subunit beta 3) This gene encodes the beta subunit of a cyclic nucleotide-gated ion channel. The encoded beta subunit appears to play a role in modulation of channel function in cone photoreceptors. This heterotetrameric channel is necessary for sensory transduction, and mutations in this gene have been associated with achromatopsia 3, progressive cone dystrophy, and juvenile macular degeneration, also known as Stargardt Disease. [provided by RefSeq, Feb 2010]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.85).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CNGB3	NM_019098.5	c.*1371G>T		3_prime_UTR_variant	18/18	ENST00000320005.6	NP_061971.3
CNGB3	XM_011517138.3	c.*1371G>T		3_prime_UTR_variant	16/16		XP_011515440.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CNGB3	ENST00000320005.6	c.*1371G>T		3_prime_UTR_variant	18/18	1	NM_019098.5	ENSP00000316605	P1
CNGB3	ENST00000517327.5	c.276+4256G>T		intron_variant		3		ENSP00000428329
CNGB3	ENST00000681546.1	n.3621G>T		non_coding_transcript_exon_variant	13/13
CNGB3	ENST00000681746.1	c.*2212G>T		3_prime_UTR_variant, NMD_transcript_variant	19/19			ENSP00000505959

Frequencies

GnomAD3 genomes AF: 0.000421 AC: 64 AN: 152162 Hom.: 1 Cov.: 32

Gnomad AFR AF: 0.0000965

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000393

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000385

Gnomad SAS AF: 0.00538

Gnomad FIN AF: 0.0000943

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000294

Gnomad OTH AF: 0.00239

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 2 Hom.: 0 Cov.: 0 AF XY: 0.00 AC XY: 0 AN XY: 2

Gnomad4 FIN exome AF: 0.00

GnomAD4 genome AF: 0.000420 AC: 64 AN: 152280 Hom.: 1 Cov.: 32 AF XY: 0.000618 AC XY: 46 AN XY: 74448

Gnomad4 AFR AF: 0.0000963

Gnomad4 AMR AF: 0.000392

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.000386

Gnomad4 SAS AF: 0.00538

Gnomad4 FIN AF: 0.0000943

Gnomad4 NFE AF: 0.000294

Gnomad4 OTH AF: 0.00237

Alfa AF: 0.000159 Hom.: 0

Bravo AF: 0.000238

Asia WGS AF: 0.000866 AC: 3 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, single submitter

Submissions by phenotype

Severe early-childhood-onset retinal dystrophy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

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, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Achromatopsia 3 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

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, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.85
CADD	Benign	0.069
DANN	Benign	0.37

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

Other links and lift over

dbSNP: rs372688369; hg19: chr8-87586661;