Variant chr4-121828396-A-G details in Genebe, Genetics Data Aggregator

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2BP4_Strong

The ENST00000264499.9(BBS7):c.1890+6T>C variant causes a splice donor region, intron change. The variant allele was found at a frequency of 0.00000124 in 1,610,858 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 6.9e-7 ( 0 hom. )

Consequence

BBS7
ENST00000264499.9 splice_donor_region, intron

Scores

Splicing: ADA: 0.5028

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 3.67

Variant links:

Genes affected

BBS7 (HGNC:18758): (Bardet-Biedl syndrome 7) This gene encodes one of eight proteins that form the BBSome complex containing BBS1, BBS2, BBS4, BBS5, BBS7, BBS8, BBS9 and BBIP10. The BBSome complex is believed to recruit Rab8(GTP) to the primary cilium and promote ciliogenesis. The BBSome complex assembly is mediated by a complex composed of three chaperonin-like BBS proteins (BBS6, BBS10, and BBS12) and CCT/TRiC family chaperonins. Mutations in this gene are implicated in Bardet-Biedl syndrome, a genetic disorder whose symptoms include obesity, retinal degeneration, polydactyly and nephropathy; however, mutations in this gene and the BBS8 gene are thought to play a minor role and mutations in chaperonin-like BBS genes are found to be a major contributor to disease development in a multiethnic Bardet-Biedl syndrome patient population. Two transcript variants encoding distinct isoforms have been identified for this gene.[provided by RefSeq, Oct 2014]

BBS7 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.55).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BBS7	NM_176824.3 linkuse as main transcript	c.1890+6T>C		splice_donor_region_variant, intron_variant		ENST00000264499.9	NP_789794.1

Ensembl

Gene	Transcript	HGVSc	Effect	TSL	MANE	Protein	Appris	UniProt
BBS7	ENST00000264499.9 linkuse as main transcript	c.1890+6T>C	splice_donor_region_variant, intron_variant	1	NM_176824.3	ENSP00000264499	P1	Q8IWZ6-1
BBS7	ENST00000506636.1 linkuse as main transcript	c.1890+6T>C	splice_donor_region_variant, intron_variant	1		ENSP00000423626		Q8IWZ6-2
BBS7	ENST00000507814.5 linkuse as main transcript	c.159+6T>C	splice_donor_region_variant, intron_variant	3		ENSP00000423250

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152234

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:

0.00

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

GnomAD4 exome

AF:

6.86e-7

AC:

AN:

1458624

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

725800

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:

9.02e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152234

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74376

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000756

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 submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 28, 2017

This sequence change falls in intron 17 of the BBS7 gene. It does not directly change the encoded amino acid sequence of the BBS7 protein, but it affects a nucleotide within the consensus splice site of the intron. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with BBS7-related disease. Nucleotide substitutions within the consensus splice site are relatively common causes of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site, but this prediction has not been confirmed by published transcriptional studies. 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

BayesDel_noAF

Benign

-0.55

CADD

Benign

DANN

Benign

0.82

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Benign

0.50

dbscSNV1_RF

Benign

0.58

SpliceAI score (max)

0.42

Details are displayed if max score is > 0.2

DS_DL_spliceai

0.42

Position offset: 6

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