18-47156193-A-G

Position:

• chr18-47156193-A-G

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PM2 PP3_Moderate PP5_Very_Strong

The NM_016097.5(IER3IP1):​c.233T>C​(p.Leu78Pro) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000192 in 1,563,768 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 Likely pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. L78L) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: IER3IP1 NM_016097.5 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 7.23

Genes affected

IER3IP1 (HGNC:18550): (immediate early response 3 interacting protein 1) This gene encodes a small protein that is localized to the endoplasmic reticulum (ER) and may play a role in the ER stress response by mediating cell differentiation and apoptosis. Transcription of this gene is regulated by tumor necrosis factor alpha and specificity protein 1 (Sp1). Mutations in this gene may play a role in microcephaly, epilepsy, and diabetes syndrome (MEDS), and a pseudogene of this gene is located on the long arm of chromosome 12. [provided by RefSeq, Dec 2011]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.844
• PP5: Variant 18-47156193-A-G is Pathogenic according to our data. Variant chr18-47156193-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 30786.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
IER3IP1	NM_016097.5	c.233T>C	p.Leu78Pro	missense_variant	3/3	ENST00000256433.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
IER3IP1	ENST00000256433.6	c.233T>C	p.Leu78Pro	missense_variant	3/3	1	NM_016097.5	P1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152184 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: 0.00

Gnomad OTH AF: 0.000478

GnomAD4 exome AF: 0.00000142 AC: 2 AN: 1411584 Hom.: 0 Cov.: 26 AF XY: 0.00 AC XY: 0 AN XY: 704874

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: 9.38e-7

Gnomad4 OTH exome AF: 0.0000170

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152184 Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1 AN XY: 74364

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.000478

Bravo AF: 0.0000189

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Microcephaly, epilepsy, and diabetes syndrome 1 Pathogenic:2

Likely pathogenic, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Mar 23, 2021	- -
Pathogenic, no assertion criteria provided	literature only	OMIM	Nov 01, 2012	- -

Microcephaly, epilepsy, and diabetes syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 07, 2022

For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). ClinVar contains an entry for this variant (Variation ID: 30786). This missense change has been observed in individuals with primary microcephaly, epilepsy, neonatal diabetes (PMID: 21835305, 22991235, 23771172, 28711742). It has also been observed to segregate with disease in related individuals. This sequence change replaces leucine, which is neutral and non-polar, with proline, which is neutral and non-polar, at codon 78 of the IER3IP1 protein (p.Leu78Pro). This variant is not present in population databases (gnomAD no frequency). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.96
BayesDel_addAF	Pathogenic	0.41	D
BayesDel_noAF	Pathogenic	0.35
CADD	Uncertain	25
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.49	T
Eigen	Uncertain	0.63
Eigen_PC	Pathogenic	0.67
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Benign	0.84	T
M_CAP	Pathogenic	0.30	D
MetaRNN	Pathogenic	0.84	D
MetaSVM	Uncertain	0.18	D
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.82	D
PROVEAN	Benign	-1.9	N
REVEL	Pathogenic	0.74
Sift	Benign	0.11	T
Sift4G	Benign	0.20	T
Polyphen		0.96	D
Vest4		0.91
MutPred		0.57		Loss of stability (P = 0.002);
MVP		0.76
MPC		0.42
ClinPred		0.99	D
GERP RS		5.9
Varity_R		0.89
gMVP		0.96

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: rs387907012; hg19: chr18-44682564;