4-57031337-C-T

Variant names:

• chr4-57031337-C-T
• rs866994863
• NM_001553.3:c.830-1G>A

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PVS1_Strong PM2 PP5_Very_Strong

The NM_001553.3(IGFBP7):​c.830-1G>A variant causes a splice acceptor, intron change. The variant was absent in control chromosomes in GnomAD project. 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 Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: IGFBP7 NM_001553.3 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 4.69

Genes affected

IGFBP7 (HGNC:5476): (insulin like growth factor binding protein 7) This gene encodes a member of the insulin-like growth factor (IGF)-binding protein (IGFBP) family. IGFBPs bind IGFs with high affinity, and regulate IGF availability in body fluids and tissues and modulate IGF binding to its receptors. This protein binds IGF-I and IGF-II with relatively low affinity, and belongs to a subfamily of low-affinity IGFBPs. It also stimulates prostacyclin production and cell adhesion. Alternatively spliced transcript variants encoding different isoforms have been described for this gene, and one variant has been associated with retinal arterial macroaneurysm (PMID:21835307). [provided by RefSeq, Dec 2011]

POLR2B (HGNC:9188): (RNA polymerase II subunit B) This gene encodes the second largest subunit of RNA polymerase II (Pol II), a DNA-dependent RNA polymerase that catalyzes the transcription of DNA into precursors of mRNA, snRNA and microRNA. This subunit and the largest subunit form opposite sides of the center cleft of Pol II. Deletion of the flap loop region of this subunit results in a decrease in the rate of transcriptional elongation. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Dec 2014]

ACMG classification

Verdict is Pathogenic. Variant got 14 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.66431093 fraction of the gene.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 4-57031337-C-T is Pathogenic according to our data. Variant chr4-57031337-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 30280.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
IGFBP7	NM_001553.3	c.830-1G>A		splice_acceptor_variant, intron_variant	Intron 4 of 4	ENST00000295666.6	NP_001544.1
POLR2B	NM_000938.3	c.*349C>T		downstream_gene_variant		ENST00000314595.6	NP_000929.1
POLR2B	NM_001303269.2	c.*349C>T		downstream_gene_variant			NP_001290198.1
POLR2B	NM_001303268.2	c.*349C>T		downstream_gene_variant			NP_001290197.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
IGFBP7	ENST00000295666.6	c.830-1G>A		splice_acceptor_variant, intron_variant	Intron 4 of 4	1	NM_001553.3	ENSP00000295666.4
POLR2B	ENST00000314595.6	c.*349C>T		downstream_gene_variant		1	NM_000938.3	ENSP00000312735.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1450244 Hom.: 0 Cov.: 28 AF XY: 0.00 AC XY: 0 AN XY: 722068

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial retinal arterial macroaneurysm Pathogenic:2

Mar 17, 2024

Genomic Medicine Center of Excellence, King Faisal Specialist Hospital and Research Centre

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: research

- -

Oct 04, 2024

Al Jalila Children’s Genomics Center, Al Jalila Childrens Speciality Hospital

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: research

PVS1,PM2,PP1 -

Retinal arterial macroaneurysm with supravascular pulmonic stenosis Pathogenic:1

Aug 12, 2011

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.62	D
BayesDel_noAF	Pathogenic	0.39
CADD	Pathogenic	32
DANN	Uncertain	1.0
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	1.0
FATHMM_MKL	Pathogenic	0.98	D
GERP RS		5.9

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.90		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.90		Position offset: -1

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

Publications

LitVar

Other links and lift over

dbSNP: rs866994863; hg19: chr4-57897503;