rs567573386

Positions:

chr16-56484820-G-A

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1_ModeratePM2PP5_Very_Strong

The NM_031885.5(BBS2):c.2107C>T(p.Arg703Ter) variant causes a stop gained change. The variant allele was found at a frequency of 0.00000929 in 1,613,992 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000089 ( 0 hom. )

Consequence

BBS2
NM_031885.5 stop_gained

Scores

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:9

Conservation

PhyloP100: 5.16

Variant links:

Genes affected

BBS2 (HGNC:967): (Bardet-Biedl syndrome 2) This gene is a member of the Bardet-Biedl syndrome (BBS) gene family. Bardet-Biedl syndrome is an autosomal recessive disorder characterized by severe pigmentary retinopathy, obesity, polydactyly, renal malformation and cognitive disability. The proteins encoded by BBS gene family members are structurally diverse and the similar phenotypes exhibited by mutations in BBS gene family members is likely due to their shared roles in cilia formation and function. Many BBS proteins localize to the basal bodies, ciliary axonemes, and pericentriolar regions of cells. BBS proteins may also be involved in intracellular trafficking via microtubule-related transport. The protein encoded by this gene forms a multiprotein BBSome complex with seven other BBS proteins.[provided by RefSeq, Oct 2014]

BBS2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 12 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 0.0272 CDS is truncated, and there are 0 pathogenic variants in the truncated region.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 16-56484820-G-A is Pathogenic according to our data. Variant chr16-56484820-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 496478.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BBS2	NM_031885.5 linkuse as main transcript	c.2107C>T	p.Arg703Ter	stop_gained	17/17	ENST00000245157.11	NP_114091.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BBS2	ENST00000245157.11 linkuse as main transcript	c.2107C>T	p.Arg703Ter	stop_gained	17/17	1	NM_031885.5	ENSP00000245157	P1

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152134

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000192

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000318

AC:

AN:

251378

Hom.:

AF XY:

0.0000442

AC XY:

AN XY:

135858

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.000272

Gnomad SAS exome

AF:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000176

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000889

AC:

AN:

1461740

Hom.:

Cov.:

AF XY:

0.00000963

AC XY:

AN XY:

727186

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.000126

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000630

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152252

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74436

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000193

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.00000993

Hom.:

Bravo

AF:

0.00000378

ExAC

AF:

0.0000330

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.000119

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:9

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Bardet-Biedl syndrome 2

Pathogenic:3

Likely pathogenic, no assertion criteria provided	clinical testing	Counsyl	May 15, 2017	- -
Likely pathogenic, no assertion criteria provided	clinical testing	Natera, Inc.	Sep 16, 2020	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Mar 20, 2024	- -

Retinitis pigmentosa 74

Pathogenic:2

Likely pathogenic, criteria provided, single submitter	clinical testing	3billion	May 22, 2022	The variant is observed at an extremely low frequency in the gnomAD v2.1.1 dataset (total allele frequency: 0.003%). Stop-gained (nonsense): predicted to result in a loss or disruption of normal protein function through protein truncation. The predicted truncated protein may be shortened by less than 10%. The variant has been reported at least twice as pathogenic with clinical assertions and evidence for the classification (ClinVar ID: VCV000496478 / PMID: 21344540). Therefore, this variant is classified as likely pathogenic according to the recommendation of ACMG/AMP guideline. -
Likely pathogenic, criteria provided, single submitter	research	Ocular Genomics Institute, Massachusetts Eye and Ear	Apr 08, 2021	The BBS2 c.2107C>T variant was identified in an individual with retinitis pigmentosa with a presumed recessive inheritance pattern. Through a review of available evidence we were able to apply the following criteria: PVS1, PM2. Based on this evidence we have classified this variant as Likely Pathogenic. -

Bardet-Biedl syndrome

Pathogenic:2

Likely pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Jun 22, 2017	- -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 11, 2024	This sequence change creates a premature translational stop signal (p.Arg703*) in the BBS2 gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 19 amino acid(s) of the BBS2 protein. This variant is present in population databases (rs567573386, gnomAD 0.03%). This premature translational stop signal has been observed in individual(s) with BBS2-related disease (PMID: 21344540, 25999675; Invitae). ClinVar contains an entry for this variant (Variation ID: 496478). For these reasons, this variant has been classified as Pathogenic. -

Inborn genetic diseases

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 24, 2017

- -

BBS2-related disorder

Pathogenic:1

Likely pathogenic, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Jan 08, 2024

The BBS2 c.2107C>T variant is predicted to result in premature protein termination (p.Arg703*). This variant has been reported in the homozygous state or with a second BBS2 variant in individuals with Bardet-Biedl syndrome (Deveault et al. 2011. PubMed ID: 21344540; Supplemental Table 1, Forsythe et al. 2016. PubMed ID: 27659767; Table S3, Fu et al. 2022. PubMed ID: 36307859) and reported in the homozygous state in an individual with retinitis pigmentosa (Xu et al. 2015. PubMed ID: 25999675). In addition, at PreventionGenetics, this variant has been seen in the homozygous or compound heterozygous states in individuals with features of Bardet-Biedl syndrome (Internal Data). This variant is reported in 0.027% of alleles in individuals of East Asian descent in a large population database. Nonsense variants in BBS2 are expected to be pathogenic. This variant is interpreted as likely pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.38

BayesDel_noAF

Pathogenic

0.62

CADD

Pathogenic

DANN

Uncertain

1.0

Eigen

Pathogenic

1.0

Eigen_PC

Pathogenic

0.87

FATHMM_MKL

Uncertain

0.92

MutationTaster

Benign

1.0

D;D

Vest4

0.48, 0.73

GERP RS

5.3

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over