rs762047808

Variant summary

Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PVS1PP5_Very_Strong

The NM_031885.5(BBS2):​c.1780C>T​(p.Arg594*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000018 in 1,613,124 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 Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000018 ( 0 hom. )

Consequence

BBS2
NM_031885.5 stop_gained

Scores

2
3
2

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:8

Conservation

PhyloP100: 3.20

Publications

1 publications found
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 Gene-Disease associations (from GenCC):
  • Bardet-Biedl syndrome 2
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae), Myriad Women’s Health
  • ciliopathy
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • retinitis pigmentosa 74
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
  • retinitis pigmentosa
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Bardet-Biedl syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 16 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PP5
Variant 16-56497760-G-A is Pathogenic according to our data. Variant chr16-56497760-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 550489.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BBS2NM_031885.5 linkc.1780C>T p.Arg594* stop_gained Exon 14 of 17 ENST00000245157.11 NP_114091.4 Q9BXC9

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BBS2ENST00000245157.11 linkc.1780C>T p.Arg594* stop_gained Exon 14 of 17 1 NM_031885.5 ENSP00000245157.5 Q9BXC9
ENSG00000288725ENST00000684388.1 linkn.700C>T non_coding_transcript_exon_variant Exon 5 of 14 ENSP00000507647.1 A0A804HJU2

Frequencies

GnomAD3 genomes
AF:
0.0000198
AC:
3
AN:
151842
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000657
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000796
AC:
2
AN:
251104
AF XY:
0.00000737
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000178
AC:
26
AN:
1461282
Hom.:
0
Cov.:
31
AF XY:
0.0000220
AC XY:
16
AN XY:
726960
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33470
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26128
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39634
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86250
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53098
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
0.0000198
AC:
22
AN:
1111834
Other (OTH)
AF:
0.0000497
AC:
3
AN:
60382
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.429
Heterozygous variant carriers
0
2
4
6
8
10
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000198
AC:
3
AN:
151842
Hom.:
0
Cov.:
32
AF XY:
0.0000270
AC XY:
2
AN XY:
74128
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41318
American (AMR)
AF:
0.0000657
AC:
1
AN:
15230
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5168
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4810
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10528
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68000
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000565
Hom.:
0
Bravo
AF:
0.0000264
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:8
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Bardet-Biedl syndrome 2 Pathogenic:5
Jan 05, 2021
Natera, Inc.
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Mar 21, 2023
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 26, 2017
Counsyl
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Nov 24, 2022
Eurofins-Biomnis
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jul 16, 2024
Genetics laboratory, Department of Obstetrics & Gynae, Institute of Kidney Diseases & Research Centre Dr. H.L. Trivedi Institute Of Transplantation Sciences
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

A compound heterozygous missense variant c.1780C>T in BBS2 (chr16:56531672; Depth:182x) gene was detected. This sequence change creates a premature translational stop signal (p.Arg594*) in the BBS2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in BBS2 are known to be pathogenic. This variant is present in population databases (rs762047808, gnomAD 0.002%). This premature translational stop signal has been observed in individual(s) with Bardet-Biedl syndrome. ClinVar contains an entry for this variant (Variation ID: 550489). Based on the aforementioned evidence, the variant is classified as a pathogenic according to the ACMG AMP classification system. -

BBS2-related disorder Pathogenic:1
Mar 22, 2024
PreventionGenetics, part of Exact Sciences
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

The BBS2 c.1780C>T variant is predicted to result in premature protein termination (p.Arg594*). This variant was reported in the compound heterozygous state in an individual with Bardet-Biedl syndrome (Bravo-Gil et al 2016. PubMed ID: 27032803). This variant is reported in 0.0023% of alleles in individuals of European (Non-Finnish) descent in gnomAD. Nonsense variants in BBS2 are expected to be pathogenic. This variant is interpreted as pathogenic. -

Bardet-Biedl syndrome 2;C4225281:Retinitis pigmentosa 74 Pathogenic:1
Dec 16, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Bardet-Biedl syndrome Pathogenic:1
Dec 02, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Arg594*) in the BBS2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in BBS2 are known to be pathogenic (PMID: 11285252, 20177705, 24608809, 26518167). This variant is present in population databases (rs762047808, gnomAD 0.002%). This premature translational stop signal has been observed in individual(s) with Bardet-Biedl syndrome (PMID: 27032803). ClinVar contains an entry for this variant (Variation ID: 550489). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.61
D
BayesDel_noAF
Pathogenic
0.60
CADD
Pathogenic
38
DANN
Uncertain
0.99
Eigen
Uncertain
0.38
Eigen_PC
Benign
0.20
FATHMM_MKL
Uncertain
0.94
D
PhyloP100
3.2
Vest4
0.95
GERP RS
1.9
Mutation Taster
=1/199
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.15
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs762047808; hg19: chr16-56531672; COSMIC: COSV55328382; COSMIC: COSV55328382; API