chr2-169479577-G-C

Variant names:

• chr2-169479577-G-C
• rs373396081
• NM_152384.3:c.24G>C

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM2 PP2 PP3_Strong

The NM_152384.3(BBS5):​c.24G>C​(p.Trp8Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,846 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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. W8R) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: BBS5 NM_152384.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.81
• Publications: 0 publications found

Genes affected

BBS5 (HGNC:970): (Bardet-Biedl syndrome 5) This gene encodes a protein that has been directly linked to Bardet-Biedl syndrome. The primary features of this syndrome include retinal dystrophy, obesity, polydactyly, renal abnormalities and learning disabilities. Experimentation in non-human eukaryotes suggests that this gene is expressed in ciliated cells and that it is required for the formation of cilia. Alternate transcriptional splice variants have been observed but have not been fully characterized. [provided by RefSeq, Jul 2008]

BBS5 Gene-Disease associations (from GenCC):

• Bardet-Biedl syndrome 5

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, Ambry Genetics, Labcorp Genetics (formerly Invitae), Laboratory for Molecular Medicine, G2P
• BBS5-related ciliopathy

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• Bardet-Biedl syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ENSG00000251569 (HGNC:):

ACMG classification

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 7 curated pathogenic missense variants (we use a threshold of 10). The gene has 1 curated benign missense variants. Gene score misZ: 0.85025 (below the threshold of 3.09). Trascript score misZ: 1.0056 (below the threshold of 3.09). GenCC associations: The gene is linked to Bardet-Biedl syndrome 5, Bardet-Biedl syndrome.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.969

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_152384.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BBS5	NM_152384.3	MANE Select	c.24G>C	p.Trp8Cys	missense	Exon 1 of 12	NP_689597.1	A0A0S2Z626

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BBS5	ENST00000295240.8	TSL:1 MANE Select	c.24G>C	p.Trp8Cys	missense	Exon 1 of 12	ENSP00000295240.3	Q8N3I7-1
	ENSG00000251569	ENST00000513963.1	TSL:2	c.24G>C	p.Trp8Cys	missense	Exon 1 of 16	ENSP00000424363.1	E9PBE3
	BBS5	ENST00000392663.6	TSL:1	c.24G>C	p.Trp8Cys	missense	Exon 1 of 11	ENSP00000376431.2	Q8N3I7-2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD2 exomes AF: 0.00000400 AC: 1 AN: 249782 AF XY: 0.00000740

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000892

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461846 Hom.: 0 Cov.: 34 AF XY: 0.00000138 AC XY: 1 AN XY: 727228

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39696

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53416

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111982

Other (OTH) AF: 0.00 AC: 0 AN: 60392

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.00233887), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 33

ExAC AF: 0.00000824 AC: 1

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Bardet-Biedl syndrome (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.41	D
BayesDel_noAF	Pathogenic	0.36
CADD	Pathogenic	32
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.73	D
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.97
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.96	D
M_CAP	Uncertain	0.25	D
MetaRNN	Pathogenic	0.97	D
MetaSVM	Uncertain	0.50	D
MutationAssessor	Pathogenic	2.9	M
PhyloP100		8.8
PROVEAN	Pathogenic	-12	D
REVEL	Pathogenic	0.83
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.87
MutPred		0.86		Gain of disorder (P = 0.0272)
MVP		0.97
MPC		1.4
ClinPred		1.0	D
GERP RS		6.0
PromoterAI		-0.0017	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.95
gMVP		0.82
Mutation Taster		=5/95	disease causing

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

Other links and lift over

dbSNP: rs373396081; hg19: chr2-170336087;