16-57882493-T-C

Variant summary

Our verdict is Benign. Variant got -14 ACMG points: 0P and 14B. BP4_Strong BP6_Moderate BS1 BS2

The NM_001297.5(CNGB1):c.*1671A>G variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0339 in 152,244 control chromosomes in the GnomAD database, including 118 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★).

• Frequency:
  • Genomes: 𝑓 0.034 (118 hom., cov: 32)
  • Failed GnomAD Quality Control
• Consequence: CNGB1 NM_001297.5 3_prime_UTR
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 0.00600

Genes affected

CNGB1 (HGNC:2151): (cyclic nucleotide gated channel subunit beta 1) In humans, the rod photoreceptor cGMP-gated cation channel helps regulate ion flow into the rod photoreceptor outer segment in response to light-induced alteration of the levels of intracellular cGMP. This channel consists of two subunits, alpha and beta, with the protein encoded by this gene representing the beta subunit. Defects in this gene are a cause of cause of retinitis pigmentosa type 45. Three transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Oct 2013]

ACMG classification

Verdict is Benign. Variant got -14 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.89).
• BP6: Variant 16-57882493-T-C is Benign according to our data. Variant chr16-57882493-T-C is described in ClinVar as [Likely_benign]. Clinvar id is 886979.Status of the report is criteria_provided_single_submitter, 1 stars.
• BS1: Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.0339 (5156/152244) while in subpopulation NFE AF= 0.0434 (2950/68012). AF 95% confidence interval is 0.0421. There are 118 homozygotes in gnomad4. There are 2532 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.
• BS2: High Homozygotes in GnomAd at 118 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CNGB1	NM_001297.5	c.*1671A>G		3_prime_UTR_variant	33/33	ENST00000251102.13
CNGB1	NM_001286130.2	c.*1671A>G		3_prime_UTR_variant	33/33

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CNGB1	ENST00000251102.13	c.*1671A>G		3_prime_UTR_variant	33/33	1	NM_001297.5	P4

Frequencies

GnomAD3 genomes AF: 0.0339 AC: 5155 AN: 152126 Hom.: 118 Cov.: 32

Gnomad AFR AF: 0.0186

Gnomad AMI AF: 0.0429

Gnomad AMR AF: 0.0304

Gnomad ASJ AF: 0.0738

Gnomad EAS AF: 0.000577

Gnomad SAS AF: 0.0212

Gnomad FIN AF: 0.0405

Gnomad MID AF: 0.127

Gnomad NFE AF: 0.0434

Gnomad OTH AF: 0.0483

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

GnomAD4 genome AF: 0.0339 AC: 5156 AN: 152244 Hom.: 118 Cov.: 32 AF XY: 0.0340 AC XY: 2532 AN XY: 74444

Gnomad4 AFR AF: 0.0186

Gnomad4 AMR AF: 0.0303

Gnomad4 ASJ AF: 0.0738

Gnomad4 EAS AF: 0.000578

Gnomad4 SAS AF: 0.0214

Gnomad4 FIN AF: 0.0405

Gnomad4 NFE AF: 0.0434

Gnomad4 OTH AF: 0.0473

Alfa AF: 0.0418 Hom.: 21

Bravo AF: 0.0325

Asia WGS AF: 0.0130 AC: 45 AN: 3478

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Retinitis pigmentosa Benign:1

Likely benign, 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 and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.89
Cadd	Benign	1.8
Dann	Benign	0.49

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: rs117526439; hg19: chr16-57916397;