4-625675-G-C

Variant names:

• chr4-625675-G-C
• rs866891056
• NM_000283.4:c.49G>C

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_000283.4(PDE6B):​c.49G>C​(p.Asp17His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,461,618 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign 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. D17N) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: PDE6B NM_000283.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -1.39
• Publications: 0 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

ACMG classification

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.13723558).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PDE6B	NM_000283.4	c.49G>C	p.Asp17His	missense_variant	Exon 1 of 22	ENST00000496514.6	NP_000274.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PDE6B	ENST00000496514.6	c.49G>C	p.Asp17His	missense_variant	Exon 1 of 22	1	NM_000283.4	ENSP00000420295.1
PDE6B	ENST00000255622.10	c.49G>C	p.Asp17His	missense_variant	Exon 1 of 22	1		ENSP00000255622.6

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461618 Hom.: 0 Cov.: 32 AF XY: 0.00000413 AC XY: 3 AN XY: 727126

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: 39696

South Asian (SAS) AF: 0.0000348 AC: 3 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53190

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

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111982

Other (OTH) AF: 0.0000166 AC: 1 AN: 60388

GnomAD4 genome Cov.: 33

Asia WGS AF: 0.000289 AC: 1 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Apr 12, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.49G>C (p.D17H) alteration is located in exon 1 (coding exon 1) of the PDE6B gene. This alteration results from a G to C substitution at nucleotide position 49, causing the aspartic acid (D) at amino acid position 17 to be replaced by a histidine (H). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.093
BayesDel_addAF	Benign	-0.19	T
BayesDel_noAF	Benign	-0.51
CADD	Benign	0.085
DANN	Benign	0.85
DEOGEN2	Benign	0.32	.;T
Eigen	Benign	-0.98
Eigen_PC	Benign	-1.1
FATHMM_MKL	Benign	0.11	N
LIST_S2	Benign	0.28	T;T
M_CAP	Benign	0.032	D
MetaRNN	Benign	0.14	T;T
MetaSVM	Benign	-0.78	T
MutationAssessor	Benign	1.1	L;L
PhyloP100		-1.4
PrimateAI	Benign	0.29	T
PROVEAN	Benign	-0.90	N;N
REVEL	Benign	0.10
Sift	Benign	0.12	T;T
Sift4G	Benign	0.12	T;T
Polyphen		0.27	B;B
Vest4		0.13
MutPred		0.26		Loss of disorder (P = 0.0885);Loss of disorder (P = 0.0885);
MVP		0.66
MPC		0.29
ClinPred		0.22	T
GERP RS		-4.4
PromoterAI		0.020	Neutral
Varity_R		0.064
gMVP		0.36
Mutation Taster		=99/1	polymorphism

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: rs866891056; hg19: chr4-619464;