chr2-162267222-CA-C

Variant names:

• chr2-162267222-CA-C
• rs1392296770
• NM_022168.4:c.3055delT

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PVS1_Moderate

The NM_022168.4(IFIH1):​c.3055delT​(p.Cys1019ValfsTer10) variant causes a frameshift change. The variant allele was found at a frequency of 0.0000182 in 1,593,974 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000017 (0 hom.)
• Consequence: IFIH1 NM_022168.4 frameshift
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.65
• 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: 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: Uncertain_significance. The variant received 2 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.00747 CDS is truncated, and there are 0 pathogenic variants in the truncated region.

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.3055delT	p.Cys1019ValfsTer10	frameshift	Exon 16 of 16	NP_071451.2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	IFIH1	ENST00000649979.2	MANE Select	c.3055delT	p.Cys1019ValfsTer10	frameshift	Exon 16 of 16	ENSP00000497271.1	Q9BYX4-1
	IFIH1	ENST00000648433.1		c.2938delT	p.Cys980ValfsTer10	frameshift	Exon 15 of 15	ENSP00000496816.1	A0A3B3IRK8
	IFIH1	ENST00000679938.1		c.2743delT	p.Cys915ValfsTer10	frameshift	Exon 15 of 15	ENSP00000505518.1	A0A7P0Z4A9

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152140 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: 0.0000588

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.0000173 AC: 25 AN: 1441834 Hom.: 0 Cov.: 30 AF XY: 0.0000167 AC XY: 12 AN XY: 716888

African (AFR) AF: 0.00 AC: 0 AN: 31942

American (AMR) AF: 0.00 AC: 0 AN: 38846

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25476

East Asian (EAS) AF: 0.00 AC: 0 AN: 39598

South Asian (SAS) AF: 0.00 AC: 0 AN: 81896

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53228

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4966

European-Non Finnish (NFE) AF: 0.0000217 AC: 24 AN: 1106292

Other (OTH) AF: 0.0000168 AC: 1 AN: 59590

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152140 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74314

African (AFR) AF: 0.00 AC: 0 AN: 41424

American (AMR) AF: 0.00 AC: 0 AN: 15272

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.00 AC: 0 AN: 5198

South Asian (SAS) AF: 0.00 AC: 0 AN: 4820

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10604

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000588 AC: 4 AN: 68032

Other (OTH) AF: 0.00 AC: 0 AN: 2094

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000151

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
PhyloP100		4.6
Mutation Taster		=21/179	disease causing

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: rs1392296770; hg19: chr2-163123732;