rs201408393

Positions:

chr22-30614345-T-C

Variant summary

Our verdict is Benign. Variant got -7 ACMG points: 2P and 9B. PM2BP4_StrongBP6BS1

The NM_000355.4(TCN2):c.428-4T>C variant causes a splice region, splice polypyrimidine tract, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000236 in 1,614,050 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.0012 ( 1 hom., cov: 32)

Exomes 𝑓: 0.00013 ( 0 hom. )

Consequence

TCN2
NM_000355.4 splice_region, splice_polypyrimidine_tract, intron

Scores

Splicing: ADA: 0.00004095

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:3

Conservation

PhyloP100: 0.0350

Variant links:

Genes affected

TCN2 (HGNC:11653): (transcobalamin 2) This gene encodes a member of the vitamin B12-binding protein family. This family of proteins, alternatively referred to as R binders, is expressed in various tissues and secretions. This plasma protein binds cobalamin and mediates the transport of cobalamin into cells. This protein and other mammalian cobalamin-binding proteins, such as transcobalamin I and gastric intrisic factor, may have evolved by duplication of a common ancestral gene. Alternative splicing results in multiple transcript variants.[provided by RefSeq, May 2010]

TCN2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -7 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.92).

BP6

Variant 22-30614345-T-C is Benign according to our data. Variant chr22-30614345-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 341194.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Benign=1, Uncertain_significance=1}.

BS1

Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.00122 (185/152226) while in subpopulation AFR AF= 0.00402 (167/41552). AF 95% confidence interval is 0.00352. There are 1 homozygotes in gnomad4. There are 89 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TCN2	NM_000355.4 linkuse as main transcript	c.428-4T>C		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		ENST00000215838.8	NP_000346.2
TCN2	NM_001184726.2 linkuse as main transcript	c.347-4T>C		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant			NP_001171655.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TCN2	ENST00000215838.8 linkuse as main transcript	c.428-4T>C		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		1	NM_000355.4	ENSP00000215838	P2	P20062-1

Frequencies

GnomAD3 genomes

AF:

0.00120

AC:

183

AN:

152108

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00398

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000983

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:

0.00144

GnomAD3 exomes

AF:

0.000275

AC:

AN:

251004

Hom.:

AF XY:

0.000206

AC XY:

AN XY:

135722

show subpopulations

Gnomad AFR exome

AF:

0.00382

Gnomad AMR exome

AF:

0.000174

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:

0.00

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.000134

AC:

196

AN:

1461824

Hom.:

Cov.:

AF XY:

0.000120

AC XY:

AN XY:

727204

show subpopulations

Gnomad4 AFR exome

AF:

0.00505

Gnomad4 AMR exome

AF:

0.000201

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:

0.00000180

Gnomad4 OTH exome

AF:

0.000265

GnomAD4 genome

AF:

0.00122

AC:

185

AN:

152226

Hom.:

Cov.:

AF XY:

0.00120

AC XY:

AN XY:

74426

show subpopulations

Gnomad4 AFR

AF:

0.00402

Gnomad4 AMR

AF:

0.000982

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:

0.00142

Alfa

AF:

0.00112

Hom.:

Bravo

AF:

0.00134

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1Benign:3

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Transcobalamin II deficiency

Uncertain:1Benign:2

Benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 30, 2024	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 13, 2018	This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
Likely benign, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Aug 10, 2023	- -

TCN2-related disorder

Benign:1

Likely benign, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Jul 14, 2019

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.92

CADD

Benign

0.36

DANN

Benign

0.50

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Benign

0.000041

dbscSNV1_RF

Benign

0.0080

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

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