2-86263981-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PM5 PP3_Moderate

The NM_001371279.1(REEP1):c.166G>A(p.Asp56Asn) 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. 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. D56H) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: REEP1 NM_001371279.1 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.86

Genes affected

REEP1 (HGNC:25786): (receptor accessory protein 1) This gene encodes a mitochondrial protein that functions to enhance the cell surface expression of odorant receptors. Mutations in this gene cause spastic paraplegia autosomal dominant type 31, a neurodegenerative disorder. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Sep 2009]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr2-86263981-C-G is described in ClinVar as [Pathogenic]. Clinvar id is 989225.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.89

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
REEP1	NM_001371279.1	c.166G>A	p.Asp56Asn	missense_variant	3/9	ENST00000538924.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
REEP1	ENST00000538924.7	c.166G>A	p.Asp56Asn	missense_variant	3/9	5	NM_001371279.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary spastic paraplegia 31 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jul 15, 2016

This sequence change replaces aspartic acid with asparagine at codon 56 of the REEP1 protein (p.Asp56Asn). The aspartic acid residue is highly conserved and there is a small physicochemical difference between aspartic acid and asparagine. This variant is not present in population databases (ExAC no frequency). This variant has been reported in a family affected with SPG31 (PMID: 21618648). An experimental study has shown that this variant does not affect cellular localization of the encoded protein, however, other protein functions were not assessed (PMID: 24478229). Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). In summary, this variant is a rare missense change with uncertain impact on protein function. Although it is absent from the population and reported in affected individuals, the available evidence is currently insufficient to determine its role in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.19	D
BayesDel_noAF	Uncertain	0.030
Cadd	Pathogenic	28
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.69	D;.;.;.;.;.;.;.
Eigen	Pathogenic	0.97
Eigen_PC	Pathogenic	0.90
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.40	D
MetaRNN	Pathogenic	0.89	D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	3.2	M;.;.;.;.;.;M;.
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Pathogenic	0.87	D
PROVEAN	Pathogenic	-5.0	D;.;.;.;.;D;D;D
REVEL	Pathogenic	0.90
Sift	Uncertain	0.0020	D;.;.;.;.;D;.;D
Sift4G	Uncertain	0.025	D;.;.;.;.;D;D;.
Polyphen		1.0	D;.;.;.;.;.;.;.
Vest4		0.83
MutPred		0.59		Loss of sheet (P = 0.0457);.;.;Loss of sheet (P = 0.0457);.;.;Loss of sheet (P = 0.0457);.;
MVP		0.91
MPC		1.9
ClinPred		1.0	D
GERP RS		5.4
Varity_R		0.90
gMVP		0.93

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: rs1060503493; hg19: chr2-86491104;