rs1131603

Variant summary

Our verdict is Benign. The variant received -20 ACMG points: 0P and 20B. BP4_StrongBP6_Very_StrongBS1BS2

The NM_000355.4(TCN2):​c.1127T>C​(p.Leu376Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0436 in 1,614,044 control chromosomes in the GnomAD database, including 1,756 homozygotes. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★).

Frequency

Genomes: 𝑓 0.036 ( 138 hom., cov: 31)
Exomes 𝑓: 0.044 ( 1618 hom. )

Consequence

TCN2
NM_000355.4 missense

Scores

6
12

Clinical Significance

Benign criteria provided, multiple submitters, no conflicts B:4O:1

Conservation

PhyloP100: 2.93

Publications

38 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: Benign. The variant received -20 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.002260387).
BP6
Variant 22-30622988-T-C is Benign according to our data. Variant chr22-30622988-T-C is described in ClinVar as [Benign]. Clinvar id is 341214.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.0363 (5529/152192) while in subpopulation NFE AF = 0.0498 (3389/67996). AF 95% confidence interval is 0.0484. There are 138 homozygotes in GnomAd4. There are 2713 alleles in the male GnomAd4 subpopulation. Median coverage is 31. This position passed quality control check.
BS2
High Homozygotes in GnomAd4 at 138 AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TCN2NM_000355.4 linkc.1127T>C p.Leu376Ser missense_variant Exon 8 of 9 ENST00000215838.8 NP_000346.2 P20062-1
TCN2NM_001184726.2 linkc.1046T>C p.Leu349Ser missense_variant Exon 8 of 9 NP_001171655.1 P20062-2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TCN2ENST00000215838.8 linkc.1127T>C p.Leu376Ser missense_variant Exon 8 of 9 1 NM_000355.4 ENSP00000215838.3 P20062-1

Frequencies

GnomAD3 genomes
AF:
0.0363
AC:
5527
AN:
152074
Hom.:
137
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.00785
Gnomad AMI
AF:
0.0407
Gnomad AMR
AF:
0.0287
Gnomad ASJ
AF:
0.0472
Gnomad EAS
AF:
0.000386
Gnomad SAS
AF:
0.0158
Gnomad FIN
AF:
0.0958
Gnomad MID
AF:
0.0253
Gnomad NFE
AF:
0.0498
Gnomad OTH
AF:
0.0340
GnomAD2 exomes
AF:
0.0422
AC:
10609
AN:
251480
AF XY:
0.0426
show subpopulations
Gnomad AFR exome
AF:
0.00794
Gnomad AMR exome
AF:
0.0217
Gnomad ASJ exome
AF:
0.0475
Gnomad EAS exome
AF:
0.000163
Gnomad FIN exome
AF:
0.0942
Gnomad NFE exome
AF:
0.0553
Gnomad OTH exome
AF:
0.0492
GnomAD4 exome
AF:
0.0444
AC:
64866
AN:
1461852
Hom.:
1618
Cov.:
31
AF XY:
0.0444
AC XY:
32302
AN XY:
727232
show subpopulations
African (AFR)
AF:
0.00633
AC:
212
AN:
33480
American (AMR)
AF:
0.0224
AC:
1004
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.0444
AC:
1160
AN:
26134
East Asian (EAS)
AF:
0.000202
AC:
8
AN:
39700
South Asian (SAS)
AF:
0.0206
AC:
1781
AN:
86258
European-Finnish (FIN)
AF:
0.0902
AC:
4820
AN:
53416
Middle Eastern (MID)
AF:
0.0433
AC:
250
AN:
5768
European-Non Finnish (NFE)
AF:
0.0478
AC:
53152
AN:
1111980
Other (OTH)
AF:
0.0410
AC:
2479
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.474
Heterozygous variant carriers
0
3536
7073
10609
14146
17682
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
1862
3724
5586
7448
9310
<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
AF:
0.0363
AC:
5529
AN:
152192
Hom.:
138
Cov.:
31
AF XY:
0.0365
AC XY:
2713
AN XY:
74392
show subpopulations
African (AFR)
AF:
0.00782
AC:
325
AN:
41536
American (AMR)
AF:
0.0286
AC:
437
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.0472
AC:
164
AN:
3472
East Asian (EAS)
AF:
0.000387
AC:
2
AN:
5164
South Asian (SAS)
AF:
0.0164
AC:
79
AN:
4816
European-Finnish (FIN)
AF:
0.0958
AC:
1017
AN:
10614
Middle Eastern (MID)
AF:
0.0272
AC:
8
AN:
294
European-Non Finnish (NFE)
AF:
0.0498
AC:
3389
AN:
67996
Other (OTH)
AF:
0.0337
AC:
71
AN:
2108
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.502
Heterozygous variant carriers
0
275
549
824
1098
1373
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
Variant carriers
0
60
120
180
240
300
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0459
Hom.:
705
Bravo
AF:
0.0316
TwinsUK
AF:
0.0442
AC:
164
ALSPAC
AF:
0.0415
AC:
160
ESP6500AA
AF:
0.00908
AC:
40
ESP6500EA
AF:
0.0501
AC:
431
ExAC
AF:
0.0427
AC:
5180
Asia WGS
AF:
0.0100
AC:
36
AN:
3478
EpiCase
AF:
0.0516
EpiControl
AF:
0.0546

ClinVar

Significance: Benign
Submissions summary: Benign:4Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Benign:2Other:1
-
GenomeConnect, ClinGen
Significance:not provided
Review Status:no classification provided
Collection Method:phenotyping only

Variant interpreted as Benign and reported on 04-27-2020 by Lab or GTR ID 500031. GenomeConnect assertions are reported exactly as they appear on the patient-provided report from the testing laboratory. GenomeConnect staff make no attempt to reinterpret the clinical significance of the variant. This variant was reported in an individual referred for clinical diagnostic genetic testing. -

Nov 15, 2018
GeneDx
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is associated with the following publications: (PMID: 28334792, 23754956) -

-
Breakthrough Genomics, Breakthrough Genomics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:not provided

- -

Transcobalamin II deficiency Benign:2
Feb 03, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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 and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.26
BayesDel_addAF
Benign
-0.44
T
BayesDel_noAF
Benign
-0.37
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Benign
0.025
T;T;T;.
Eigen
Uncertain
0.32
Eigen_PC
Uncertain
0.31
FATHMM_MKL
Uncertain
0.80
D
LIST_S2
Benign
0.66
T;T;T;T
MetaRNN
Benign
0.0023
T;T;T;T
MetaSVM
Benign
-1.1
T
MutationAssessor
Benign
1.7
L;.;.;.
PhyloP100
2.9
PrimateAI
Benign
0.47
T
PROVEAN
Benign
-0.69
N;.;N;N
REVEL
Benign
0.14
Sift
Uncertain
0.013
D;.;D;T
Sift4G
Uncertain
0.0020
D;D;D;D
Polyphen
1.0
D;.;D;.
Vest4
0.22
MPC
0.055
ClinPred
0.0060
T
GERP RS
5.5
Varity_R
0.59
gMVP
0.66
Mutation Taster
=45/55
polymorphism (auto)

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: rs1131603; hg19: chr22-31018975; COSMIC: COSV107232709; API