rs74162087

Variant names:

• chr2-162272383-C-A
• rs74162087
• NM_022168.4:c.2459G>T

Your query was ambiguous. Multiple possible variants found:

• chr2-162272383-C-A
• chr2-162272383-C-G
• chr2-162272383-C-T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_022168.4(IFIH1):​c.2459G>T​(p.Arg820Leu) variant causes a missense change. The variant allele was found at a frequency of 0.000000685 in 1,459,302 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. R820S) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: IFIH1 NM_022168.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.84
• Publications: 5 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: Labcorp Genetics (formerly Invitae), G2P, Illumina
• IFIH1-related type 1 interferonopathy

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

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
• 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: Likely_pathogenic. The variant received 6 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 10 uncertain in NM_022168.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.866

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.2459G>T	p.Arg820Leu	missense	Exon 13 of 16	NP_071451.2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	IFIH1	ENST00000649979.2	MANE Select	c.2459G>T	p.Arg820Leu	missense	Exon 13 of 16	ENSP00000497271.1	Q9BYX4-1
	IFIH1	ENST00000648433.1		c.2342G>T	p.Arg781Leu	missense	Exon 12 of 15	ENSP00000496816.1	A0A3B3IRK8
	IFIH1	ENST00000679938.1		c.2147G>T	p.Arg716Leu	missense	Exon 12 of 15	ENSP00000505518.1	A0A7P0Z4A9

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1459302 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 725950

African (AFR) AF: 0.00 AC: 0 AN: 33322

American (AMR) AF: 0.00 AC: 0 AN: 43886

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26052

East Asian (EAS) AF: 0.0000252 AC: 1 AN: 39676

South Asian (SAS) AF: 0.00 AC: 0 AN: 86090

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53366

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5748

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1110874

Other (OTH) AF: 0.00 AC: 0 AN: 60288

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

ClinVar submissions

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	Uncertain	0.44
BayesDel_addAF	Pathogenic	0.34	D
BayesDel_noAF	Pathogenic	0.25
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.56	D
Eigen	Pathogenic	0.89
Eigen_PC	Pathogenic	0.84
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.94	D
M_CAP	Uncertain	0.18	D
MetaRNN	Pathogenic	0.87	D
MetaSVM	Uncertain	0.44	D
MutationAssessor	Benign	1.8	L
PhyloP100		5.8
PrimateAI	Uncertain	0.54	T
PROVEAN	Pathogenic	-5.3	D
REVEL	Pathogenic	0.79
Sift	Uncertain	0.0040	D
Sift4G	Uncertain	0.0080	D
Polyphen		1.0	D
Vest4		0.85
MutPred		0.60		Loss of methylation at R820 (P = 0.0087)
MVP		0.83
MPC		0.22
ClinPred		0.99	D
GERP RS		5.6
Varity_R		0.91
gMVP		0.78
Mutation Taster		=72/28	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: rs74162087; hg19: chr2-163128893;