chr2-169479570-C-A

Position:

• chr2-169479570-C-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_152384.3(BBS5):​c.17C>A​(p.Ala6Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: BBS5 NM_152384.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.39

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.36078763).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BBS5	NM_152384.3	c.17C>A	p.Ala6Glu	missense_variant	1/12	ENST00000295240.8	NP_689597.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BBS5	ENST00000295240.8	c.17C>A	p.Ala6Glu	missense_variant	1/12	1	NM_152384.3	ENSP00000295240	P1
BBS5	ENST00000392663.6	c.17C>A	p.Ala6Glu	missense_variant	1/11	1		ENSP00000376431
BBS5	ENST00000469980.1	n.91C>A		non_coding_transcript_exon_variant	1/2	4
BBS5	ENST00000443151.1	c.17C>A	p.Ala6Glu	missense_variant, NMD_transcript_variant	1/6	5		ENSP00000406182

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Bardet-Biedl syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 19, 2022

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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. This variant has not been reported in the literature in individuals affected with BBS5-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces alanine, which is neutral and non-polar, with glutamic acid, which is acidic and polar, at codon 6 of the BBS5 protein (p.Ala6Glu). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.26
BayesDel_addAF	Uncertain	0.064	T
BayesDel_noAF	Benign	-0.15
CADD	Benign	21
DANN	Uncertain	0.99
DEOGEN2	Benign	0.13	T;.;.
Eigen	Uncertain	0.21
Eigen_PC	Uncertain	0.30
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.91	D;D;D
M_CAP	Benign	0.049	D
MetaRNN	Benign	0.36	T;T;T
MetaSVM	Benign	-0.46	T
MutationAssessor	Benign	1.3	L;L;.
MutationTaster	Benign	0.98	D;D;D
PROVEAN	Benign	-1.4	N;N;N
REVEL	Uncertain	0.40
Sift	Benign	0.065	T;D;D
Sift4G	Benign	0.85	T;T;T
Polyphen		0.35	B;P;.
Vest4		0.39
MutPred		0.68		Gain of disorder (P = 0.0175);Gain of disorder (P = 0.0175);Gain of disorder (P = 0.0175);
MVP		0.86
MPC		0.62
ClinPred		0.94	D
GERP RS		5.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.0
Varity_R		0.20
gMVP		0.31

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr2-170336080;