rs672601336

Variant names:

• chr2-162281369-C-G
• rs672601336
• NM_022168.4:c.1483G>C

Your query was ambiguous. Multiple possible variants found:

• chr2-162281369-C-G
• chr2-162281369-C-T

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PS1_Very_Strong PM2

The NM_022168.4(IFIH1):​c.1483G>C​(p.Gly495Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Likely pathogenic in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G495A) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: IFIH1 NM_022168.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.19
• Publications: 0 publications found

Genes affected

IFIH1 (HGNC:18873): (interferon induced with helicase C domain 1) IFIH1 encodes MDA5 which is an intracellular sensor of viral RNA that triggers the innate immune response. Sensing RNA length and secondary structure, MDA5 binds dsRNA oligonucleotides with a modified DExD/H-box helicase core and a C-terminal domain, thus leading to a proinflammatory response that includes interferons. It has been shown that Coronaviruses (CoVs) as well as various other virus families, are capable of evading the MDA5-dependent interferon response, thus impeding the activation of the innate immune response to infection. MDA5 has also been shown to play an important role in enhancing natural killer cell function in malaria infection. In addition to its protective role in antiviral responses, MDA5 has been implicated in autoimmune and autoinflammatory diseases such as type 1 diabetes, systemic lupus erythematosus, and Aicardi-Goutieres syndrome[provided by RefSeq, Jul 2020]

IFIH1 Gene-Disease associations (from GenCC):

• Aicardi-Goutieres syndrome 7

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Illumina, G2P, Labcorp Genetics (formerly Invitae)
• IFIH1-related type 1 interferonopathy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• Singleton-Merten syndrome 1

  Inheritance: AD Classification: STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• Aicardi-Goutieres syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Singleton-Merten dysplasia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• immunodeficiency 95

  Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PS1: Transcript NM_022168.4 (IFIH1) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar.
• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_022168.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	IFIH1	NM_022168.4	MANE Select	c.1483G>C	p.Gly495Arg	missense	Exon 7 of 16	NP_071451.2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	IFIH1	ENST00000649979.2	MANE Select	c.1483G>C	p.Gly495Arg	missense	Exon 7 of 16	ENSP00000497271.1	Q9BYX4-1
	IFIH1	ENST00000648433.1		c.1483G>C	p.Gly495Arg	missense	Exon 7 of 15	ENSP00000496816.1	A0A3B3IRK8
	IFIH1	ENST00000679938.1		c.1171G>C	p.Gly391Arg	missense	Exon 6 of 15	ENSP00000505518.1	A0A7P0Z4A9

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Aicardi-Goutieres syndrome 7;C4225427:Singleton-Merten syndrome 1 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.13
BayesDel_addAF	Benign	-0.12	T
BayesDel_noAF	Benign	-0.41
CADD	Uncertain	24
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.44	T
Eigen	Uncertain	0.60
Eigen_PC	Uncertain	0.55
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.92	D
M_CAP	Uncertain	0.10	D
MetaRNN	Uncertain	0.65	D
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	2.0	M
PhyloP100		3.2
PrimateAI	Uncertain	0.52	T
PROVEAN	Pathogenic	-5.4	D
REVEL	Pathogenic	0.72
Sift	Benign	0.037	D
Sift4G	Benign	0.070	T
Polyphen		0.98	D
Vest4		0.45
MutPred		0.54		Loss of ubiquitination at K498 (P = 0.0236)
MVP		0.68
MPC		0.049
ClinPred		0.94	D
GERP RS		4.0
Varity_R		0.38
gMVP		0.71
Mutation Taster		=32/68	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs672601336; hg19: chr2-163137879;