15-72735890-C-G

Variant names:

• chr15-72735890-C-G
• rs1419955498
• NM_033028.5:c.1172C>G

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_033028.5(BBS4):​c.1172C>G​(p.Ala391Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A391T) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: BBS4 NM_033028.5 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.56
• Publications: 0 publications found

Genes affected

BBS4 (HGNC:969): (Bardet-Biedl syndrome 4) 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. The similar phenotypes exhibited by mutations in BBS gene family members are likely due to the protein's 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 has sequence similarity to O-linked N-acetylglucosamine (O-GlcNAc) transferases in plants and archaebacteria and in human forms a multi-protein "BBSome" complex with seven other BBS proteins. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Mar 2016]

BBS4 Gene-Disease associations (from GenCC):

• Bardet-Biedl syndrome 4

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, G2P
• BBS4-related ciliopathy

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

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.811

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_033028.5. 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
	BBS4	NM_033028.5	MANE Select	c.1172C>G	p.Ala391Gly	missense	Exon 14 of 16	NP_149017.2
	BBS4	NM_001320665.2		c.1103C>G	p.Ala368Gly	missense	Exon 13 of 15	NP_001307594.1	H3BSL2
	BBS4	NM_001252678.2		c.656C>G	p.Ala219Gly	missense	Exon 13 of 15	NP_001239607.1	Q96RK4-3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BBS4	ENST00000268057.9	TSL:1 MANE Select	c.1172C>G	p.Ala391Gly	missense	Exon 14 of 16	ENSP00000268057.4	Q96RK4-1
	BBS4	ENST00000395205.7	TSL:1	c.656C>G	p.Ala219Gly	missense	Exon 13 of 15	ENSP00000378631.3	Q96RK4-3
	BBS4	ENST00000566400.6	TSL:1	c.656C>G	p.Ala219Gly	missense	Exon 13 of 15	ENSP00000456759.2	H3BSL3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.28
BayesDel_addAF	Pathogenic	0.29	D
BayesDel_noAF	Pathogenic	0.18
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.75	D
Eigen	Pathogenic	0.73
Eigen_PC	Pathogenic	0.71
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.93	D
M_CAP	Benign	0.080	D
MetaRNN	Pathogenic	0.81	D
MetaSVM	Uncertain	0.76	D
MutationAssessor	Pathogenic	3.3	M
PhyloP100		7.6
PrimateAI	Benign	0.39	T
PROVEAN	Uncertain	-3.2	D
REVEL	Pathogenic	0.70
Sift	Uncertain	0.011	D
Sift4G	Uncertain	0.018	D
Polyphen		0.99	D
Vest4		0.73
MutPred		0.58		Gain of ubiquitination at K388 (P = 0.1028)
MVP		0.90
MPC		0.078
ClinPred		0.99	D
GERP RS		5.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.47
gMVP		0.38
Mutation Taster		=31/69	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
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

Other links and lift over

dbSNP: rs1419955498; hg19: chr15-73028231;