rs147738100

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2PP3_Strong

The NM_000355.4(TCN2):​c.737C>A​(p.Thr246Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,862 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T246I) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

TCN2
NM_000355.4 missense

Scores

2
10
7

Clinical Significance

Not reported in ClinVar

Conservation

PhyloP100: 0.848

Publications

0 publications found
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 Gene-Disease associations (from GenCC):
  • transcobalamin II deficiency
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae), Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.971

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TCN2NM_000355.4 linkc.737C>A p.Thr246Asn missense_variant Exon 5 of 9 ENST00000215838.8 NP_000346.2
TCN2NM_001184726.2 linkc.656C>A p.Thr219Asn missense_variant Exon 5 of 9 NP_001171655.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TCN2ENST00000215838.8 linkc.737C>A p.Thr246Asn missense_variant Exon 5 of 9 1 NM_000355.4 ENSP00000215838.3

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461862
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
727226
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53390
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1112010
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.46
BayesDel_addAF
Uncertain
0.020
T
BayesDel_noAF
Benign
-0.21
CADD
Uncertain
24
DANN
Uncertain
0.99
DEOGEN2
Benign
0.34
T;T;T;.
Eigen
Uncertain
0.34
Eigen_PC
Uncertain
0.28
FATHMM_MKL
Benign
0.65
D
LIST_S2
Benign
0.79
T;T;T;T
M_CAP
Uncertain
0.10
D
MetaRNN
Pathogenic
0.97
D;D;D;D
MetaSVM
Benign
-0.48
T
MutationAssessor
Pathogenic
3.1
M;.;.;.
PhyloP100
0.85
PrimateAI
Benign
0.42
T
PROVEAN
Uncertain
-4.3
D;.;D;D
REVEL
Uncertain
0.30
Sift
Uncertain
0.0030
D;.;D;D
Sift4G
Uncertain
0.015
D;D;D;D
Polyphen
0.94
P;.;P;.
Vest4
0.80
MutPred
0.92
Gain of sheet (P = 0.0344);.;.;.;
MVP
0.64
MPC
0.054
ClinPred
0.97
D
GERP RS
3.6
Varity_R
0.84
gMVP
0.89
Mutation Taster
=16/84
disease causing

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

Other links and lift over

dbSNP: rs147738100; hg19: chr22-31011444; API