4-663143-G-C

Variant names:

• chr4-663143-G-C
• rs758052437
• NM_000283.4:c.1876G>C

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PM1 PM2 PP3

The NM_000283.4(PDE6B):​c.1876G>C​(p.Glu626Gln) 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.

• Frequency: Genomes: not found (cov: 32)
• Consequence: PDE6B NM_000283.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 9.17
• Publications: 2 publications found

Genes affected

PDE6B (HGNC:8786): (phosphodiesterase 6B) Photon absorption triggers a signaling cascade in rod photoreceptors that activates cGMP phosphodiesterase (PDE), resulting in the rapid hydrolysis of cGMP, closure of cGMP-gated cation channels, and hyperpolarization of the cell. PDE is a peripheral membrane heterotrimeric enzyme made up of alpha, beta, and gamma subunits. This gene encodes the beta subunit. Mutations in this gene result in retinitis pigmentosa and autosomal dominant congenital stationary night blindness. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Feb 2009]

PDE6B Gene-Disease associations (from GenCC):

• retinitis pigmentosa 40

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Laboratory for Molecular Medicine
• congenital stationary night blindness autosomal dominant 2

  Inheritance: AD Classification: STRONG, LIMITED Submitted by: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• congenital stationary night blindness

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• retinitis pigmentosa

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ENSG00000272927 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 5 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 8 uncertain in NM_000283.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PDE6B	NM_000283.4	c.1876G>C	p.Glu626Gln	missense_variant	Exon 15 of 22	ENST00000496514.6	NP_000274.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PDE6B	ENST00000496514.6	c.1876G>C	p.Glu626Gln	missense_variant	Exon 15 of 22	1	NM_000283.4	ENSP00000420295.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251244 AF XY: 0.00

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome Cov.: 29

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ExAC AF: 0.00000824 AC: 1

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.31	D
BayesDel_noAF	Pathogenic	0.38
CADD	Pathogenic	35
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.93	.;D;.
Eigen	Pathogenic	0.90
Eigen_PC	Pathogenic	0.78
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.95	D;D;D
M_CAP	Pathogenic	0.32	D
MetaRNN	Pathogenic	0.98	D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	4.1	H;H;.
PhyloP100		9.2
PrimateAI	Uncertain	0.78	T
PROVEAN	Uncertain	-2.7	D;D;D
REVEL	Pathogenic	0.92
Sift	Pathogenic	0.0	D;D;D
Sift4G	Uncertain	0.0030	D;D;D
Polyphen		1.0	D;D;.
Vest4		0.95
MutPred		0.92		Loss of disorder (P = 0.1147);Loss of disorder (P = 0.1147);.;
MVP		0.98
MPC		0.52
ClinPred		0.99	D
GERP RS		4.2
Varity_R		0.86
gMVP		0.91
Mutation Taster		=25/75	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.64		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.64		Position offset: 3

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs758052437; hg19: chr4-656932;