rs749017489

Variant names:

• chr15-72731423-G-C
• rs749017489
• NM_033028.5:c.830G>C

Your query was ambiguous. Multiple possible variants found:

• chr15-72731423-G-C
• chr15-72731423-G-T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2 PM5 PP3_Moderate

The NM_033028.5(BBS4):​c.830G>C​(p.Gly277Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,888 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. G277V) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 29)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: BBS4 NM_033028.5 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.83
• 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
• ciliopathy

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

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr15-72731423-G-T is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 412297.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.882

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

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BBS4	NM_033028.5	MANE Select	c.830G>C	p.Gly277Ala	missense	Exon 11 of 16	NP_149017.2
	BBS4	NM_001320665.2		c.761G>C	p.Gly254Ala	missense	Exon 10 of 15	NP_001307594.1
	BBS4	NM_001252678.2		c.314G>C	p.Gly105Ala	missense	Exon 10 of 15	NP_001239607.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BBS4	ENST00000268057.9	TSL:1 MANE Select	c.830G>C	p.Gly277Ala	missense	Exon 11 of 16	ENSP00000268057.4
	BBS4	ENST00000395205.7	TSL:1	c.314G>C	p.Gly105Ala	missense	Exon 10 of 15	ENSP00000378631.3
	BBS4	ENST00000566400.6	TSL:1	c.314G>C	p.Gly105Ala	missense	Exon 10 of 15	ENSP00000456759.2

Frequencies

GnomAD3 genomes Cov.: 29

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461888 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727244

African (AFR) AF: 0.00 AC: 0 AN: 33480

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

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53418

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

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112012

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 29

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.50
BayesDel_addAF	Uncertain	0.12	D
BayesDel_noAF	Uncertain	-0.070
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.79	D
Eigen	Pathogenic	0.86
Eigen_PC	Pathogenic	0.85
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.96	D
M_CAP	Benign	0.035	D
MetaRNN	Pathogenic	0.88	D
MetaSVM	Uncertain	0.18	D
MutationAssessor	Benign	1.9	L
PhyloP100		7.8
PrimateAI	Pathogenic	0.87	D
PROVEAN	Pathogenic	-4.5	D
REVEL	Uncertain	0.64
Sift	Benign	0.039	D
Sift4G	Benign	0.14	T
Polyphen		0.99	D
Vest4		0.74
MutPred		0.75		Gain of catalytic residue at G277 (P = 0.0867)
MVP		0.87
MPC		0.045
ClinPred		0.98	D
GERP RS		5.8
PromoterAI		-0.047	Neutral
Varity_R		0.75
gMVP		0.89
Mutation Taster		=25/75	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: rs749017489; hg19: chr15-73023764;