7-33349108-T-C

Variant names:

• chr7-33349108-T-C
• rs762511626
• NM_198428.3:c.1370T>C

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_198428.3(BBS9):​c.1370T>C​(p.Leu457Ser) variant causes a missense change. The variant allele was found at a frequency of 0.00000342 in 1,461,056 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 Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: BBS9 NM_198428.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 5.51

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 Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.895

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BBS9	NM_198428.3	c.1370T>C	p.Leu457Ser	missense_variant	Exon 13 of 23	ENST00000242067.11	NP_940820.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BBS9	ENST00000242067.11	c.1370T>C	p.Leu457Ser	missense_variant	Exon 13 of 23	1	NM_198428.3	ENSP00000242067.6

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461056 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 726874

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: 0.00000450

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000282 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Bardet-Biedl syndrome 9 Uncertain:1

Oct 30, 2021

Fulgent Genetics, Fulgent Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Bardet-Biedl syndrome Uncertain:1

Mar 04, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces leucine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 457 of the BBS9 protein (p.Leu457Ser). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with BBS9-related conditions. ClinVar contains an entry for this variant (Variation ID: 1007872). 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 BBS9 protein function with a positive predictive value of 80%. 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	0.92
BayesDel_addAF	Pathogenic	0.30	D
BayesDel_noAF	Pathogenic	0.20
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Benign	0.15	T;.;.;.
Eigen	Uncertain	0.53
Eigen_PC	Uncertain	0.48
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Uncertain	0.88	D;D;D;D
M_CAP	Uncertain	0.098	D
MetaRNN	Pathogenic	0.90	D;D;D;D
MetaSVM	Uncertain	-0.17	T
MutationAssessor	Uncertain	2.3	M;M;M;M
PrimateAI	Uncertain	0.51	T
PROVEAN	Uncertain	-3.1	D;D;D;D
REVEL	Uncertain	0.38
Sift	Uncertain	0.0010	D;D;D;D
Sift4G	Uncertain	0.013	D;D;D;D
Polyphen		1.0	D;P;D;.
Vest4		0.94
MutPred		0.67		Gain of relative solvent accessibility (P = 0.0082);Gain of relative solvent accessibility (P = 0.0082);Gain of relative solvent accessibility (P = 0.0082);Gain of relative solvent accessibility (P = 0.0082);
MVP		0.87
MPC		0.44
ClinPred		0.97	D
GERP RS		5.4
Varity_R		0.74
gMVP		0.80

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: rs762511626; hg19: chr7-33388720;