rs137852858

Positions:

• chr7-33336487-C-T

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The ENST00000242067.11(BBS9):​c.1063C>T​(p.Gln355Ter) variant causes a stop gained change. The variant allele was found at a frequency of 0.0000103 in 1,461,444 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 (★★). Synonymous variant affecting the same amino acid position (i.e. Q355Q) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000010 (0 hom.)
• Consequence: BBS9 ENST00000242067.11 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:6
• Conservation: PhyloP100: 5.41

Genes affected

BBS9 (HGNC:30000): (Bardet-Biedl syndrome 9) This gene is downregulated by parathyroid hormone in osteoblastic cells, and therefore is thought to be involved in parathyroid hormone action in bones. The exact function of this gene has not yet been determined. Alternatively spliced transcript variants encoding different isoforms have been identified. [provided by RefSeq, Jan 2017]

ACMG classification

Verdict is Pathogenic. Variant got 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 7-33336487-C-T is Pathogenic according to our data. Variant chr7-33336487-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 2660.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr7-33336487-C-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BBS9	NM_198428.3	c.1063C>T	p.Gln355Ter	stop_gained	10/23	ENST00000242067.11	NP_940820.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BBS9	ENST00000242067.11	c.1063C>T	p.Gln355Ter	stop_gained	10/23	1	NM_198428.3	ENSP00000242067	P3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.0000103 AC: 15 AN: 1461444 Hom.: 0 Cov.: 30 AF XY: 0.00000825 AC XY: 6 AN XY: 727020

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: 0.0000135

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:6

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Bardet-Biedl syndrome 9 Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Sep 11, 2023	- -
Pathogenic, no assertion criteria provided	literature only	OMIM	Dec 01, 2005	- -

Bardet-Biedl syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Feb 01, 2023	For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 2660). This premature translational stop signal has been observed in individual(s) with Bardet-Biedl syndrome (PMID: 16380913, 31456290). It has also been observed to segregate with disease in related individuals. This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Gln355*) in the BBS9 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in BBS9 are known to be pathogenic (PMID: 16380913, 20177705). -
Pathogenic, no assertion criteria provided	research	Sharon lab, Hadassah-Hebrew University Medical Center	Jun 23, 2019	- -

BBS9-related disorder Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Apr 01, 2024

The BBS9 c.1063C>T variant is predicted to result in premature protein termination (p.Gln355*). This variant has been reported in the homozygous state in two siblings with Bardet-Biedl syndrome (BBS, Nishimura et al. 2005. PubMed ID: 16380913). It has also been reported in 2 additional families with BBS, but no clinical details were provided (Sharon et al. 2019. PubMed ID: 31456290).This variant has not been reported in a large population database, indicating this variant is rare. Nonsense variants in BBS9 are expected to be pathogenic. This variant is interpreted as pathogenic. -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Oct 12, 2022

Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 25525159, 31456290, 16380913) -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.63
CADD	Pathogenic	41
DANN	Uncertain	1.0
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.88
FATHMM_MKL	Uncertain	0.97	D
MutationTaster	Benign	1.0	A;A;A;A;A
Vest4		0.55
GERP RS		5.4

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

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

Publications

LitVar

Other links and lift over

dbSNP: rs137852858; hg19: chr7-33376099;