NM_006269.2:c.2255C>A

Variant names:

• chr8-54626137-C-A
• rs28399531
• NM_006269.2:c.2255C>A

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_006269.2(RP1):​c.2255C>A​(p.Thr752Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,460,794 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T752M) has been classified as Benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: RP1 NM_006269.2 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -1.84
• Publications: 5 publications found

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]

RP1 Gene-Disease associations (from GenCC):

• RP1-related dominant retinopathy

  Inheritance: AD, SD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, ClinGen
• retinitis pigmentosa 1

  Inheritance: AR, AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Illumina, Labcorp Genetics (formerly Invitae), Ambry Genetics
• RP1-related recessive retinopathy

  Inheritance: AR Classification: DEFINITIVE Submitted by: Ambry Genetics, ClinGen
• retinitis pigmentosa

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.0498915).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
RP1	NM_006269.2	c.2255C>A	p.Thr752Lys	missense_variant	Exon 4 of 4	ENST00000220676.2	NP_006260.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
RP1	ENST00000220676.2	c.2255C>A	p.Thr752Lys	missense_variant	Exon 4 of 4	1	NM_006269.2	ENSP00000220676.1
RP1	ENST00000637698.1	c.787+3849C>A		intron_variant	Intron 3 of 28	5		ENSP00000490104.1
RP1	ENST00000636932.1	c.787+3849C>A		intron_variant	Intron 3 of 22	5		ENSP00000489857.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1460794 Hom.: 0 Cov.: 34 AF XY: 0.00000138 AC XY: 1 AN XY: 726686

African (AFR) AF: 0.00 AC: 0 AN: 33454

American (AMR) AF: 0.00 AC: 0 AN: 44690

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26112

East Asian (EAS) AF: 0.00 AC: 0 AN: 39654

South Asian (SAS) AF: 0.00 AC: 0 AN: 86104

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53198

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5730

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1111512

Other (OTH) AF: 0.00 AC: 0 AN: 60340

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.096
BayesDel_addAF	Benign	-0.42	T
BayesDel_noAF	Benign	-0.84
CADD	Benign	0.0020
DANN	Benign	0.29
DEOGEN2	Benign	0.042	T
Eigen	Benign	-2.0
Eigen_PC	Benign	-2.1
FATHMM_MKL	Benign	0.013	N
LIST_S2	Benign	0.30	T
M_CAP	Benign	0.0035	T
MetaRNN	Benign	0.050	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.34	N
PhyloP100		-1.8
PrimateAI	Benign	0.23	T
PROVEAN	Benign	-0.33	N
REVEL	Benign	0.040
Sift	Benign	0.33	T
Sift4G	Benign	1.0	T
Polyphen		0.0030	B
Vest4		0.050
MutPred		0.11		Gain of MoRF binding (P = 0.0256);
MVP		0.12
MPC		0.032
ClinPred		0.24	T
GERP RS		-12
Varity_R		0.037
gMVP		0.30
Mutation Taster		=95/5	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: rs28399531; hg19: chr8-55538697;