12-112907118-C-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_016816.4(OAS1):c.79C>T(p.Arg27Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000198 in 1,614,164 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign 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. R27H) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000021 (0 hom.)
• Consequence: OAS1 NM_016816.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.0850

Genes affected

OAS1 (HGNC:8086): (2'-5'-oligoadenylate synthetase 1) This interferon-induced gene encodes a protein that synthesizes 2',5'-oligoadenylates (2-5As). This protein plays a key role in innate cellular antiviral response, and has been implicated in other cellular processes like cell growth and apoptosis. Alternative splicing results in multiple transcript variants with different enzymatic activities. Polymorphisms in this gene have been associated with susceptibility to viral infection, including SARS-CoV-2, and diabetes mellitus, type 1. This gene is located in a cluster of related genes on chromosome 12. [provided by RefSeq, May 2022]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.12399471).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
OAS1	NM_016816.4	c.79C>T	p.Arg27Cys	missense_variant	1/6	ENST00000202917.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
OAS1	ENST00000202917.10	c.79C>T	p.Arg27Cys	missense_variant	1/6	1	NM_016816.4	P2

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152154 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000119 AC: 3 AN: 251452 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135902

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000212 AC: 31 AN: 1461892 Hom.: 0 Cov.: 31 AF XY: 0.0000179 AC XY: 13 AN XY: 727246

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.0000232

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000207

Gnomad4 OTH exome AF: 0.0000662

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152272 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74438

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000564 Hom.: 0

Bravo AF: 0.0000113

ExAC AF: 0.0000165 AC: 2

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Aug 22, 2023

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 27 of the OAS1 protein (p.Arg27Cys). This variant is present in population databases (rs117835961, gnomAD 0.006%). This variant has not been reported in the literature in individuals affected with OAS1-related conditions. ClinVar contains an entry for this variant (Variation ID: 2184057). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be tolerated. 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	0.16
BayesDel_addAF	Benign	-0.25	T
BayesDel_noAF	Benign	-0.43
Cadd	Benign	19
Dann	Benign	0.90
DEOGEN2	Benign	0.057	T;.;.;T;.;.;.
Eigen	Benign	-0.41
Eigen_PC	Benign	-0.50
FATHMM_MKL	Benign	0.62	D
LIST_S2	Benign	0.68	T;T;T;T;T;T;T
M_CAP	Benign	0.0072	T
MetaRNN	Benign	0.12	T;T;T;T;T;T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Uncertain	2.2	M;M;M;.;.;.;.
MutationTaster	Benign	1.0	N;N;N;N;N;N
PrimateAI	Benign	0.36	T
PROVEAN	Uncertain	-3.5	D;D;D;D;D;D;D
REVEL	Benign	0.11
Sift	Benign	0.054	T;T;D;D;T;D;D
Sift4G	Uncertain	0.053	T;D;D;T;D;T;D
Polyphen		0.41	B;B;B;.;D;.;.
Vest4		0.14
MVP		0.44
MPC		0.41
ClinPred		0.93	D
GERP RS		3.1
Varity_R		0.20
gMVP		0.17

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: rs117835961; hg19: chr12-113344923;