20-37184191-G-A

Position:

• chr20-37184191-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_002951.5(RPN2):​c.25G>A​(p.Val9Ile) 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. 14/21 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: RPN2 NM_002951.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.98

Genes affected

RPN2 (HGNC:10382): (ribophorin II) This gene encodes a type I integral membrane protein found only in the rough endoplasmic reticulum. The encoded protein is part of an N-oligosaccharyl transferase complex that links high mannose oligosaccharides to asparagine residues found in the Asn-X-Ser/Thr consensus motif of nascent polypeptide chains. This protein is similar in sequence to the yeast oligosaccharyl transferase subunit SWP1. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Oct 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.14005393).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
RPN2	NM_002951.5	c.25G>A	p.Val9Ile	missense_variant	2/17	ENST00000237530.11	NP_002942.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
RPN2	ENST00000237530.11	c.25G>A	p.Val9Ile	missense_variant	2/17	1	NM_002951.5	ENSP00000237530	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Congenital disorder of glycosylation Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 15, 2024

This sequence change replaces valine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 9 of the RPN2 protein (p.Val9Ile). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with RPN2-related conditions. ClinVar contains an entry for this variant (Variation ID: 2193956). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available". The isoleucine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. In summary, the available evidence is currently insufficient to determine the role of this variant 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	Benign	0.073
BayesDel_addAF	Benign	-0.21	T
BayesDel_noAF	Benign	-0.54
CADD	Benign	20
DANN	Uncertain	0.99
DEOGEN2	Benign	0.060	T;.;T
Eigen	Benign	-0.39
Eigen_PC	Benign	-0.19
FATHMM_MKL	Benign	0.69	D
LIST_S2	Benign	0.74	T;T;T
M_CAP	Benign	0.0024	T
MetaRNN	Benign	0.14	T;T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	-0.69	N;N;.
MutationTaster	Benign	1.0	N;N
PrimateAI	Benign	0.41	T
PROVEAN	Benign	0.070	N;N;N
REVEL	Benign	0.063
Sift	Benign	0.17	T;T;T
Sift4G	Benign	0.77	T;T;T
Polyphen		0.0010	B;.;.
Vest4		0.24
MutPred		0.63		Loss of catalytic residue at V9 (P = 0.0276);Loss of catalytic residue at V9 (P = 0.0276);Loss of catalytic residue at V9 (P = 0.0276);
MVP		0.41
MPC		0.13
ClinPred		0.27	T
GERP RS		2.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.030
gMVP		0.31

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: rs2066950298; hg19: chr20-35812594;