NM_019098.5:c.2221delG

Variant names:

• chr8-86576012-TC-T
• rs1554604552
• NM_019098.5:c.2221delG

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PVS1_Moderate PM2 PP5

The NM_019098.5(CNGB3):​c.2221delG​(p.Asp741IlefsTer88) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: CNGB3 NM_019098.5 frameshift
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:3 U:1
• Conservation: PhyloP100: 0.0310
• Publications: 0 publications found

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]

CNGB3 Gene-Disease associations (from GenCC):

• achromatopsia 3

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, PanelApp Australia
• CNGB3-related retinopathy

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• cone dystrophy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• achromatopsia

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• severe early-childhood-onset retinal dystrophy

  Inheritance: Unknown Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Uncertain_significance. The variant received 5 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.086 CDS is truncated, and there are 3 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 8-86576012-TC-T is Pathogenic according to our data. Variant chr8-86576012-TC-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 427667.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_019098.5. 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
	CNGB3	NM_019098.5	MANE Select	c.2221delG	p.Asp741IlefsTer88	frameshift	Exon 18 of 18	NP_061971.3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CNGB3	ENST00000320005.6	TSL:1 MANE Select	c.2221delG	p.Asp741IlefsTer88	frameshift	Exon 18 of 18	ENSP00000316605.5
	CNGB3	ENST00000517327.5	TSL:3	c.276+2676delG		intron	N/A	ENSP00000428329.1
	CNGB3	ENST00000681546.1		n.2041delG		non_coding_transcript_exon	Exon 13 of 13

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions as Germline

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
2	-	-	Achromatopsia 3 (2)
-	1	-	not provided (1)
1	-	-	Retinal dystrophy (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		0.031
Mutation Taster		=41/159	disease causing (ClinVar)

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: rs1554604552; hg19: chr8-87588240;