rs144274375

Positions:

• chr2-162277494-A-C
• chr2-162277494-A-G
• chr2-162277494-A-T

Variant summary

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

The NM_022168.4(IFIH1):​c.1965T>G​(p.Asp655Glu) 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. 15/21 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 32)
• Consequence: IFIH1 NM_022168.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.0650

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]

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=0.0709368).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
IFIH1	NM_022168.4	c.1965T>G	p.Asp655Glu	missense_variant	10/16	ENST00000649979.2	NP_071451.2
IFIH1	XM_047445407.1	c.1248T>G	p.Asp416Glu	missense_variant	9/15		XP_047301363.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
IFIH1	ENST00000649979.2	c.1965T>G	p.Asp655Glu	missense_variant	10/16		NM_022168.4	ENSP00000497271	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 26

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.10
BayesDel_addAF	Benign	-0.30	T
BayesDel_noAF	Benign	-0.66
CADD	Benign	2.2
DANN	Benign	0.39
DEOGEN2	Benign	0.042	T;T;.
Eigen	Benign	-0.93
Eigen_PC	Benign	-1.0
FATHMM_MKL	Benign	0.30	N
LIST_S2	Benign	0.40	.;T;T
M_CAP	Benign	0.0046	T
MetaRNN	Benign	0.071	T;T;T
MetaSVM	Benign	-0.92	T
MutationAssessor	Benign	1.9	L;L;.
MutationTaster	Benign	1.0	N;N
PrimateAI	Benign	0.26	T
PROVEAN	Benign	-0.26	.;N;.
REVEL	Benign	0.0050
Sift	Benign	0.43	.;T;.
Sift4G	Benign	0.53	.;T;.
Polyphen		0.18	B;B;.
Vest4		0.13
MutPred		0.34		Gain of catalytic residue at D655 (P = 0.1025);Gain of catalytic residue at D655 (P = 0.1025);.;
MVP		0.38
MPC		0.029
ClinPred		0.028	T
GERP RS		0.76
Varity_R		0.022
gMVP		0.13

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: rs144274375; hg19: chr2-163134004;