17-8014701-G-C

Position:

• chr17-8014701-G-C

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM2 PM5 PP3_Moderate PP5_Very_Strong

The NM_000180.4(GUCY2D):​c.2513G>C​(p.Arg838Pro) 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. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R838G) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 31)
• Consequence: GUCY2D NM_000180.4 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 10.0

Genes affected

GUCY2D (HGNC:4689): (guanylate cyclase 2D, retinal) This gene encodes a retina-specific guanylate cyclase, which is a member of the membrane guanylyl cyclase family. Like other membrane guanylyl cyclases, this enzyme has a hydrophobic amino-terminal signal sequence followed by a large extracellular domain, a single membrane spanning domain, a kinase homology domain, and a guanylyl cyclase catalytic domain. In contrast to other membrane guanylyl cyclases, this enzyme is not activated by natriuretic peptides. Mutations in this gene result in Leber congenital amaurosis and cone-rod dystrophy-6 diseases. [provided by RefSeq, Dec 2008]

ENSG00000279174 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 14 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chrnull-null-null-null is described in UniProt as null.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.932
• PP5: Variant 17-8014701-G-C is Pathogenic according to our data. Variant chr17-8014701-G-C is described in ClinVar as [Pathogenic]. Clinvar id is 811743.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr17-8014701-G-C is described in Lovd as [Likely_pathogenic]. Variant chr17-8014701-G-C is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
GUCY2D	NM_000180.4	c.2513G>C	p.Arg838Pro	missense_variant	13/20	ENST00000254854.5	NP_000171.1
GUCY2D	XM_011523816.2	c.2513G>C	p.Arg838Pro	missense_variant	12/19		XP_011522118.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
GUCY2D	ENST00000254854.5	c.2513G>C	p.Arg838Pro	missense_variant	13/20	1	NM_000180.4	ENSP00000254854.4
ENSG00000279174	ENST00000623126.1	n.1678C>G		non_coding_transcript_exon_variant	1/1	6

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 31

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories

Sep 01, 2018

The GUCY2D c.2513G>C; p.Arg838Pro variant is reported in the medical literature in individuals and families with autosomal dominant cone-rod dystrophy, cone dystrophy, and macular degeneration (Garcia-Hoyos 2011, Jiang 2015, Xu 2013). The variant is reported as occurring de novo in at least one affected individual and segregates with disease in other families (Garcia-Hoyos 2011, Jiang 2015, Xu 2013). Additionally, other variants at this codon (p.Ag838Cys, p.Arg838Gly, p.Arg838His) have also been reported in affected individuals (Jiang 2015, Kitiratschky 2008). The p.Arg838Pro variant is absent from general population databases (1000 Genomes Project, Exome Variant Server, and Genome Aggregation Database), indicating it is not a common polymorphism. The arginine is highly conserved and computational analyses (SIFT, PolyPhen-2) predict that this variant is deleterious. In agreement with this prediction, arginine 838 has been shown to be critical for calcium binding and protein dimerization and other variants in this codon disrupt this critical function in vitro (Ramamurthy 2001). Considering available information, this variant is classified as pathogenic. Pathogenic GUCY2D variants are causative for autosomal dominant or recessive cone-rod dystrophy (MIM: 601777) or autosomal recessive Leber congenital amaurosis (MIM: 204000). Most pathogenic variants associated with GUCY2D autosomal dominant cone degeneration or cone-rod degeneration occur in amino acid residue p.Arg838 (Kitiratschky 2008). References: Garcia-Hoyos M et al. Mutation analysis at codon 838 of the Guanylate Cyclase 2D gene in Spanish families with autosomal dominant cone, cone-rod, and macular dystrophies. Mol Vis. 2011 Apr 29;17:1103-9. Jiang F et al. GUCY2D mutations in a Chinese cohort with autosomal dominant cone or cone-rod dystrophies. Doc Ophthalmol. 2015 Oct;131(2):105-14 . Kitiratschky VB et al. Mutation analysis identifies GUCY2D as the major gene responsible for autosomal dominant progressive cone degeneration. Invest Ophthalmol Vis Sci 2008 Nov;49(11):5015-5023. Ramamurthy V et al. Interactions within the coiled-coil domain of RetGC-1 guanylyl cyclase are optimized for regulation rather than for high affinity. J Biol Chem. 2001 Jul 13;276(28):26218-29. Xu F et a. Phenotypic characterization of a Chinese family with autosomal dominant cone-rod dystrophy related to GUCY2D. Doc Ophthalmol. 2013 Jun;126(3):233-40. -

Cone-rod dystrophy 6;C2931258:Leber congenital amaurosis 1 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 22, 2024

This sequence change replaces arginine, which is basic and polar, with proline, which is neutral and non-polar, at codon 838 of the GUCY2D protein (p.Arg838Pro). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with cone-rod dystrophy (PMID: 26298565). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 811743). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed for this missense variant. However, the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on GUCY2D protein function. This variant disrupts the p.Arg838 amino acid residue in GUCY2D. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 9618177, 15175914, 26298565). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Retinal dystrophy Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Blueprint Genetics

Dec 19, 2018

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.47	D
BayesDel_noAF	Pathogenic	0.43
CADD	Pathogenic	33
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.91	D
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.99
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.72	D
MetaRNN	Pathogenic	0.93	D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	3.9	H
PrimateAI	Pathogenic	0.80	T
PROVEAN	Pathogenic	-6.7	D
REVEL	Pathogenic	0.87
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.98
MutPred		0.58		Loss of solvent accessibility (P = 0.0404);
MVP		0.98
MPC		2.1
ClinPred		1.0	D
GERP RS		5.0
Varity_R		0.98
gMVP		0.99

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

LitVar

Other links and lift over

dbSNP: rs61750173; hg19: chr17-7918019;