rs148808295

Variant summary

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

The NM_031885.5(BBS2):​c.358G>A​(p.Ala120Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000601 in 1,613,830 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.00028 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000038 ( 0 hom. )

Consequence

BBS2
NM_031885.5 missense

Scores

4
8
6

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 7.79

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: Uncertain_significance. The variant received 0 ACMG points.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BBS2NM_031885.5 linkc.358G>A p.Ala120Thr missense_variant Exon 3 of 17 ENST00000245157.11 NP_114091.4 Q9BXC9

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BBS2ENST00000245157.11 linkc.358G>A p.Ala120Thr missense_variant Exon 3 of 17 1 NM_031885.5 ENSP00000245157.5 Q9BXC9

Frequencies

GnomAD3 genomes
AF:
0.000276
AC:
42
AN:
152110
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000845
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
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:
0.0000735
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.0000796
AC:
20
AN:
251246
AF XY:
0.0000515
show subpopulations
Gnomad AFR exome
AF:
0.00105
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000880
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000376
AC:
55
AN:
1461720
Hom.:
0
Cov.:
33
AF XY:
0.0000344
AC XY:
25
AN XY:
727158
show subpopulations
African (AFR)
AF:
0.00119
AC:
40
AN:
33476
American (AMR)
AF:
0.0000447
AC:
2
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39692
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53330
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000719
AC:
8
AN:
1111946
Other (OTH)
AF:
0.0000828
AC:
5
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.472
Heterozygous variant carriers
0
3
6
9
12
15
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:
0.000276
AC:
42
AN:
152110
Hom.:
0
Cov.:
32
AF XY:
0.000337
AC XY:
25
AN XY:
74292
show subpopulations
African (AFR)
AF:
0.000845
AC:
35
AN:
41420
American (AMR)
AF:
0.0000655
AC:
1
AN:
15266
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4816
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10604
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000735
AC:
5
AN:
68020
Other (OTH)
AF:
0.000478
AC:
1
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.494
Heterozygous variant carriers
0
3
5
8
10
13
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:
0.000137
Hom.:
0
Bravo
AF:
0.000370
ESP6500AA
AF:
0.00114
AC:
5
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.000107
AC:
13
EpiCase
AF:
0.000109
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Inborn genetic diseases Uncertain:1
May 16, 2022
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.358G>A (p.A120T) alteration is located in exon 3 (coding exon 3) of the BBS2 gene. This alteration results from a G to A substitution at nucleotide position 358, causing the alanine (A) at amino acid position 120 to be replaced by a threonine (T). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Bardet-Biedl syndrome 2 Uncertain:1
Oct 28, 2019
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

BBS2-related disorder Uncertain:1
Feb 15, 2024
PreventionGenetics, part of Exact Sciences
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

The BBS2 c.358G>A variant is predicted to result in the amino acid substitution p.Ala120Thr. To our knowledge, this variant has not been reported in the literature. This variant is reported in 0.092% of alleles in individuals of African descent in gnomAD, which may be too common to be an undocumented primary cause of disease. Although we suspect that this variant may be benign, at this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Bardet-Biedl syndrome 2;C4225281:Retinitis pigmentosa 74 Uncertain:1
Mar 22, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Bardet-Biedl syndrome Uncertain:1
Oct 17, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 120 of the BBS2 protein (p.Ala120Thr). This variant is present in population databases (rs148808295, gnomAD 0.1%). This variant has not been reported in the literature in individuals affected with BBS2-related conditions. ClinVar contains an entry for this variant (Variation ID: 410986). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt BBS2 protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.15
BayesDel_addAF
Benign
-0.014
T
BayesDel_noAF
Pathogenic
0.16
CADD
Pathogenic
27
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.51
D;.
Eigen
Pathogenic
0.75
Eigen_PC
Pathogenic
0.78
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.86
D;.
M_CAP
Uncertain
0.18
D
MetaRNN
Uncertain
0.54
D;D
MetaSVM
Uncertain
0.27
D
PhyloP100
7.8
PrimateAI
Uncertain
0.64
T
PROVEAN
Benign
-1.6
N;N
REVEL
Uncertain
0.64
Sift
Benign
0.034
D;D
Sift4G
Benign
0.063
T;T
Vest4
0.83
MVP
0.84
MPC
0.69
ClinPred
0.13
T
GERP RS
5.9
gMVP
0.64
Mutation Taster
=21/79
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.060
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: rs148808295; hg19: chr16-56545184; API