2-162288134-C-T

Position:

chr2-162288134-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PVS1

The NM_022168.4(IFIH1):c.1095+1G>A variant causes a splice donor, intron change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000587 in 1,585,614 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000059 ( 0 hom. )

Consequence

IFIH1
NM_022168.4 splice_donor, intron

Scores

Splicing: ADA: 1.000

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 7.57

Variant links:

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 links:

IFIH1 (HGNC:):

IFIH1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

PVS1

Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
IFIH1	NM_022168.4 linkuse as main transcript	c.1095+1G>A		splice_donor_variant, intron_variant		ENST00000649979.2	NP_071451.2	Q9BYX4-1
IFIH1	XM_047445407.1 linkuse as main transcript	c.378+1G>A		splice_donor_variant, intron_variant			XP_047301363.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
IFIH1	ENST00000649979.2 linkuse as main transcript	c.1095+1G>A		splice_donor_variant, intron_variant			NM_022168.4	ENSP00000497271.1		Q9BYX4-1

Frequencies

GnomAD3 genomes

AF:

0.0000527

AC:

AN:

151824

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000484

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000657

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:

0.0000736

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000240

AC:

AN:

249856

Hom.:

AF XY:

0.0000296

AC XY:

AN XY:

135082

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000291

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000355

Gnomad OTH exome

AF:

0.000165

GnomAD4 exome

AF:

0.0000593

AC:

AN:

1433790

Hom.:

Cov.:

AF XY:

0.0000629

AC XY:

AN XY:

715002

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000753

Gnomad4 OTH exome

AF:

0.0000506

GnomAD4 genome

AF:

0.0000527

AC:

AN:

151824

Hom.:

Cov.:

AF XY:

0.0000675

AC XY:

AN XY:

74122

show subpopulations

Gnomad4 AFR

AF:

0.0000484

Gnomad4 AMR

AF:

0.0000657

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000736

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000340

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000116

AC:

ExAC

AF:

0.00000824

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Mayo Clinic Laboratories, Mayo Clinic	Jun 13, 2023	- -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	May 10, 2019	Canonical splice site variant in a gene for which loss-of-function is not a known mechanism of disease; Has not been previously published as pathogenic or benign to our knowledge -

Aicardi-Goutieres syndrome 7;C4225427:Singleton-Merten syndrome 1;C5676929:Immunodeficiency 95

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Jul 16, 2021

- -

Aicardi-Goutieres syndrome 7;C4225427:Singleton-Merten syndrome 1

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 02, 2024

This sequence change affects a donor splice site in intron 5 of the IFIH1 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), however the current clinical and genetic evidence is not sufficient to establish whether loss-of-function variants in IFIH1 cause disease. This variant is present in population databases (rs140125523, gnomAD 0.006%). This variant has not been reported in the literature in individuals affected with IFIH1-related conditions. ClinVar contains an entry for this variant (Variation ID: 1305619). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. 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

BayesDel_addAF

Pathogenic

0.39

BayesDel_noAF

Pathogenic

0.43

CADD

Pathogenic

DANN

Uncertain

1.0

Eigen

Pathogenic

1.2

Eigen_PC

Pathogenic

1.1

FATHMM_MKL

Pathogenic

0.99

GERP RS

6.0

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.95

SpliceAI score (max)

0.85

Details are displayed if max score is > 0.2

DS_DL_spliceai

0.85

Position offset: 1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over