16-56502807-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2PP3

The NM_031885.5(BBS2):ā€‹c.806T>Cā€‹(p.Val269Ala) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,874 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (ā˜…).

Frequency

Genomes: not found (cov: 32)
Exomes š‘“: 6.8e-7 ( 0 hom. )

Consequence

BBS2
NM_031885.5 missense, splice_region

Scores

6
10
2
Splicing: ADA: 0.3501
2

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 9.29
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 3 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.815

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
BBS2NM_031885.5 linkuse as main transcriptc.806T>C p.Val269Ala missense_variant, splice_region_variant 8/17 ENST00000245157.11 NP_114091.4 Q9BXC9

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
BBS2ENST00000245157.11 linkuse as main transcriptc.806T>C p.Val269Ala missense_variant, splice_region_variant 8/171 NM_031885.5 ENSP00000245157.5 Q9BXC9

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461874
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
727234
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
8.99e-7
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
Cov.:
32

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Bardet-Biedl syndrome Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpAug 31, 2021This sequence change replaces valine with alanine at codon 269 of the BBS2 protein (p.Val269Ala). The valine residue is highly conserved and there is a small physicochemical difference between valine and alanine. This variant is not present in population databases (ExAC no frequency). This missense change has been observed in individual(s) with clinical features of retinitis pigmentosa (Invitae). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. 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
Pathogenic
0.59
BayesDel_addAF
Pathogenic
0.17
D
BayesDel_noAF
Uncertain
0.010
CADD
Pathogenic
28
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.83
D;.
Eigen
Uncertain
0.68
Eigen_PC
Pathogenic
0.72
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.95
D;.
M_CAP
Benign
0.045
D
MetaRNN
Pathogenic
0.81
D;D
MetaSVM
Uncertain
-0.24
T
PrimateAI
Uncertain
0.65
T
PROVEAN
Uncertain
-3.6
D;D
REVEL
Uncertain
0.59
Sift
Uncertain
0.0050
D;D
Sift4G
Uncertain
0.0050
D;D
Vest4
0.80
MutPred
0.50
Loss of sheet (P = 0.0228);Loss of sheet (P = 0.0228);
MVP
0.75
MPC
0.74
ClinPred
0.99
D
GERP RS
5.9
gMVP
0.51

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.35
dbscSNV1_RF
Benign
0.53
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

No publications associated with this variant yet.

Other links and lift over

hg19: chr16-56536719; COSMIC: COSV99802354; COSMIC: COSV99802354; API