rs104894417

Variant names:

• chr13-48261222-T-A
• rs104894417
• NM_021999.5:c.799T>A
• ITM2B p.Ter267Argext*?

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PM2 PM4 PP5

The NM_021999.5(ITM2B):​c.799T>A​(p.Ter267Argext*?) variant causes a stop lost change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Pathogenic (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: ITM2B NM_021999.5 stop_lost
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 3.89
• Publications: 8 publications found

Genes affected

ITM2B (HGNC:6174): (integral membrane protein 2B) Amyloid precursor proteins are processed by beta-secretase and gamma-secretase to produce beta-amyloid peptides which form the characteristic plaques of Alzheimer disease. This gene encodes a transmembrane protein which is processed at the C-terminus by furin or furin-like proteases to produce a small secreted peptide which inhibits the deposition of beta-amyloid. Mutations which result in extension of the C-terminal end of the encoded protein, thereby increasing the size of the secreted peptide, are associated with two neurogenerative diseases, familial British dementia and familial Danish dementia. [provided by RefSeq, Oct 2009]

ITM2B Gene-Disease associations (from GenCC):

• ABri amyloidosis

  Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp
• ADan amyloidosis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• retinal dystrophy with inner retinal dysfunction and ganglion cell anomalies

  Inheritance: AD Classification: SUPPORTIVE, LIMITED Submitted by: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae), Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM4: Stoplost variant in NM_021999.5 Downstream stopcodon found after 317 codons.
• PP5: Variant 13-48261222-T-A is Pathogenic according to our data. Variant chr13-48261222-T-A is described in ClinVar as Pathogenic. ClinVar VariationId is 5979.Status of the report is no_assertion_criteria_provided, 0 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_021999.5. 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
	ITM2B	NM_021999.5	MANE Select	c.799T>A	p.Ter267Argext*?	stop_lost	Exon 6 of 6	NP_068839.1	Q9Y287-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ITM2B	ENST00000647800.2	MANE Select	c.799T>A	p.Ter267Argext*?	stop_lost	Exon 6 of 6	ENSP00000497221.1	Q9Y287-1
	ITM2B	ENST00000970638.1		c.865T>A	p.Ter289Argext*?	stop_lost	Exon 7 of 7	ENSP00000640697.1
	ITM2B	ENST00000899433.1		c.763T>A	p.Ter255Argext*?	stop_lost	Exon 6 of 6	ENSP00000569492.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 27

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
1	-	-	ABri amyloidosis (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Benign	0.0066	T
BayesDel_noAF	Benign	-0.23
CADD	Benign	18
DANN	Benign	0.80
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.87
FATHMM_MKL	Uncertain	0.96	D
PhyloP100		3.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Mutation Taster		=9/191	disease causing (ClinVar)

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

dbSNP: rs104894417;

hg19: chr13-48835358;