8-54620989-G-T

Position:

• chr8-54620989-G-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_006269.2(RP1):​c.23G>T​(p.Gly8Val) 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. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: RP1 NM_006269.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.18

Genes affected

RP1 (HGNC:10263): (RP1 axonemal microtubule associated) This gene encodes a member of the doublecortin family. The protein encoded by this gene contains two doublecortin domains, which bind microtubules and regulate microtubule polymerization. The encoded protein is a photoreceptor microtubule-associated protein and is required for correct stacking of outer segment disc. This protein and the RP1L1 protein, another retinal-specific protein, play essential and synergistic roles in affecting photosensitivity and outer segment morphogenesis of rod photoreceptors. Because of its response to in vivo retinal oxygen levels, this protein was initially named ORP1 (oxygen-regulated protein-1). This protein was subsequently designated RP1 (retinitis pigmentosa 1) when it was found that mutations in this gene cause autosomal dominant retinitis pigmentosa. Mutations in this gene also cause autosomal recessive retinitis pigmentosa. Transcript variants resulted from an alternative promoter and alternative splicings have been found, which overlap the current reference sequence and has several exons upstream and downstream of the current reference sequence. However, the biological validity and full-length nature of some variants cannot be determined at this time.[provided by RefSeq, Sep 2010]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.067116946).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
RP1	NM_006269.2	c.23G>T	p.Gly8Val	missense_variant	2/4	ENST00000220676.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
RP1	ENST00000220676.2	c.23G>T	p.Gly8Val	missense_variant	2/4	1	NM_006269.2
RP1	ENST00000637698.1	c.23G>T	p.Gly8Val	missense_variant	2/29	5		P1
RP1	ENST00000636932.1	c.23G>T	p.Gly8Val	missense_variant	2/23	5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 02, 2021

The c.23G>T (p.G8V) alteration is located in exon 2 (coding exon 1) of the RP1 gene. This alteration results from a G to T substitution at nucleotide position 23, causing the glycine (G) at amino acid position 8 to be replaced by a valine (V). 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	0.089
BayesDel_addAF	Benign	-0.32	T
BayesDel_noAF	Benign	-0.70
CADD	Benign	18
DANN	Benign	0.93
Eigen	Benign	-0.88
Eigen_PC	Benign	-0.75
FATHMM_MKL	Uncertain	0.89	D
LIST_S2	Benign	0.56	T;T;T
M_CAP	Benign	0.0078	T
MetaRNN	Benign	0.067	T;T;T
MetaSVM	Benign	-1.0	T
MutationTaster	Benign	1.0	N
PrimateAI	Benign	0.29	T
Polyphen		0.0	.;B;.
Vest4		0.10
MutPred		0.16		Loss of loop (P = 0.1258);Loss of loop (P = 0.1258);Loss of loop (P = 0.1258);
MVP		0.32
MPC		0.032
ClinPred		0.29	T
GERP RS		2.2
Varity_R		0.057
gMVP		0.31

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.15		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: chr8-55533549; COSMIC: COSV55123824;