rs786204444

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_024649.5(BBS1):​c.436C>T​(p.Arg146*) variant causes a stop gained change. The variant allele was found at a frequency of 0.00000805 in 1,613,988 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 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000075 ( 0 hom. )

Consequence

BBS1
NM_024649.5 stop_gained

Scores

2
4
1

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:10

Conservation

PhyloP100: 3.79

Publications

10 publications found
Variant links:
Genes affected
BBS1 (HGNC:966): (Bardet-Biedl syndrome 1) Mutations in this gene have been observed in patients with the major form (type 1) of Bardet-Biedl syndrome. The encoded protein may play a role in eye, limb, cardiac and reproductive system development. [provided by RefSeq, Jul 2008]
BBS1 Gene-Disease associations (from GenCC):
  • Bardet-Biedl syndrome 1
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, G2P, Myriad Women’s Health, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
  • ciliopathy
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • 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 18 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 11-66515543-C-T is Pathogenic according to our data. Variant chr11-66515543-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 188752.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
BBS1NM_024649.5 linkc.436C>T p.Arg146* stop_gained Exon 5 of 17 ENST00000318312.12 NP_078925.3 Q8NFJ9-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BBS1ENST00000318312.12 linkc.436C>T p.Arg146* stop_gained Exon 5 of 17 1 NM_024649.5 ENSP00000317469.7 Q8NFJ9-1
ENSG00000256349ENST00000419755.3 linkc.547C>T p.Arg183* stop_gained Exon 5 of 17 2 ENSP00000398526.3

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152114
Hom.:
0
Cov.:
32
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:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000795
AC:
2
AN:
251458
AF XY:
0.00000736
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:
0.0000462
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000752
AC:
11
AN:
1461874
Hom.:
0
Cov.:
33
AF XY:
0.00000963
AC XY:
7
AN XY:
727240
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.0000187
AC:
1
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5758
European-Non Finnish (NFE)
AF:
0.00000719
AC:
8
AN:
1112010
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.434
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.0000131
AC:
2
AN:
152114
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74298
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.0000241
AC:
1
AN:
41414
American (AMR)
AF:
0.00
AC:
0
AN:
15260
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4822
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68014
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.0448430), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.350
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.00
Hom.:
0
Bravo
AF:
0.0000151

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:10
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Bardet-Biedl syndrome Pathogenic:4
Jan 23, 2025
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.Arg146*) in the BBS1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in BBS1 are known to be pathogenic (PMID: 12118255, 21520335, 27032803). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This premature translational stop signal has been observed in individuals with Bardet-Biedl syndrome (PMID: 12677556, 12920096, 18327255, 20177705, 21052717). ClinVar contains an entry for this variant (Variation ID: 188752). For these reasons, this variant has been classified as Pathogenic. -

Apr 08, 2014
Counsyl
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

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. -

Sep 15, 2018
Laboratory of Medical Genetics (UMR_S 1112), INSERM/Strasbourg University
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:provider interpretation

- -

Sep 24, 2018
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: BBS1 c.436C>T (p.Arg146X) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. The variant allele was found at a frequency of 8.1e-06 in 246238 control chromosomes (gnomAD). c.436C>T has been reported in the literature in multiple individuals affected with Bardet-Biedl Syndrome (Beales_2003, Fauser_2003, M'Hanmdi_2014). These data indicate that the variant is very likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. A ClinVar submission from a clinical diagnostic laboratory (evaluation after 2014) cites the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Bardet-Biedl syndrome 1 Pathogenic:3
Mar 26, 2024
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Sep 16, 2020
Natera, Inc.
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Feb 12, 2022
Fulgent Genetics, Fulgent Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Pathogenic:1
Apr 26, 2018
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The R146X variant in the BBS1 gene has been reported previously in the homozygous and compound heterozygous state in multiple individuals with Bardet-Biedl syndrome (M'hamdi et al., 2014; Muller et al., 2010; Leitch et al., 2008). This variant is predicted to cause loss of normal protein function either through protein truncation or nonsense-mediated mRNA decay. The R146X variant is observed in 1/22300 (0.004%) alleles from individuals of Finnish background (Lek et al., 2016). We interpret R146X as a pathogenic variant. -

BBS1-related disorder Pathogenic:1
Dec 29, 2023
PreventionGenetics, part of Exact Sciences
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

The BBS1 c.436C>T variant is predicted to result in premature protein termination (p.Arg146*). This variant was reported in the homozygous and compound heterozygous states in individuals with Bardet-Biedl syndrome (Beales et al. 2003. PubMed ID: 12677556; Leitch et al. 2008. PubMed ID: 18327255; Muller et al. 2010. PubMed ID: 20177705; M'hamdi et al. 2014. PubMed ID: 23432027). This variant is reported in 0.0040% of alleles in individuals of European (Finnish) descent in gnomAD. Nonsense variants in BBS1 are expected to be pathogenic. This variant is interpreted as pathogenic. -

Retinal dystrophy Pathogenic:1
Jan 01, 2009
Institute of Human Genetics, Univ. Regensburg, Univ. Regensburg
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.63
D
BayesDel_noAF
Pathogenic
0.59
CADD
Pathogenic
35
DANN
Uncertain
0.99
Eigen
Uncertain
0.45
Eigen_PC
Uncertain
0.25
FATHMM_MKL
Uncertain
0.95
D
PhyloP100
3.8
Vest4
0.37
GERP RS
4.3
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Mutation Taster
=2/198
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
Splicevardb
2.0
SpliceAI score (max)
0.010
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: rs786204444; hg19: chr11-66283014; API