chr14-24261827-G-A

Variant summary

Our verdict is Pathogenic. The variant received 15 ACMG points: 15P and 0B. PM2PM5PP2PP3_ModeratePP5_Very_Strong

The NM_000359.3(TGM1):​c.376C>T​(p.Arg126Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000366 in 1,613,932 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R126H) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000035 ( 0 hom. )

Consequence

TGM1
NM_000359.3 missense

Scores

8
7
3

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:6U:1

Conservation

PhyloP100: 1.46

Publications

7 publications found
Variant links:
Genes affected
TGM1 (HGNC:11777): (transglutaminase 1) The protein encoded by this gene is a membrane protein that catalyzes the addition of an alkyl group from an akylamine to a glutamine residue of a protein, forming an alkylglutamine in the protein. This protein alkylation leads to crosslinking of proteins and catenation of polyamines to proteins. This gene contains either one or two copies of a 22 nt repeat unit in its 3' UTR. Mutations in this gene have been associated with autosomal recessive lamellar ichthyosis (LI) and nonbullous congenital ichthyosiform erythroderma (NCIE). [provided by RefSeq, Jul 2008]
TGM1 Gene-Disease associations (from GenCC):
  • autosomal recessive congenital ichthyosis 1
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Myriad Women’s Health, PanelApp Australia, Genomics England PanelApp
  • acral self-healing collodion baby
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • bathing suit ichthyosis
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • congenital non-bullous ichthyosiform erythroderma
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • lamellar ichthyosis
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • self-healing collodion baby
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 15 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr14-24261826-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 279909.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 81 curated pathogenic missense variants (we use a threshold of 10). The gene has 20 curated benign missense variants. Gene score misZ: -0.060191 (below the threshold of 3.09). Trascript score misZ: 1.7514 (below the threshold of 3.09). GenCC associations: The gene is linked to autosomal recessive congenital ichthyosis 1, acral self-healing collodion baby, bathing suit ichthyosis, congenital non-bullous ichthyosiform erythroderma, lamellar ichthyosis, self-healing collodion baby.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.907
PP5
Variant 14-24261827-G-A is Pathogenic according to our data. Variant chr14-24261827-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 39528.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
TGM1NM_000359.3 linkc.376C>T p.Arg126Cys missense_variant Exon 3 of 15 ENST00000206765.11 NP_000350.1 P22735-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TGM1ENST00000206765.11 linkc.376C>T p.Arg126Cys missense_variant Exon 3 of 15 1 NM_000359.3 ENSP00000206765.6 P22735-1
TGM1ENST00000558074.1 linkc.376C>T p.Arg126Cys missense_variant Exon 4 of 4 5 ENSP00000453840.1 H0YN27
TGM1ENST00000544573.5 linkc.-29+300C>T intron_variant Intron 2 of 8 2 ENSP00000439446.1 P22735-2

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152134
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000196
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:
0.0000294
Gnomad OTH
AF:
0.000958
GnomAD2 exomes
AF:
0.0000279
AC:
7
AN:
251168
AF XY:
0.0000221
show subpopulations
Gnomad AFR exome
AF:
0.0000617
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000463
Gnomad NFE exome
AF:
0.0000352
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000349
AC:
51
AN:
1461798
Hom.:
0
Cov.:
32
AF XY:
0.0000289
AC XY:
21
AN XY:
727206
show subpopulations
African (AFR)
AF:
0.0000597
AC:
2
AN:
33480
American (AMR)
AF:
0.0000224
AC:
1
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.0000383
AC:
1
AN:
26136
East Asian (EAS)
AF:
0.0000504
AC:
2
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.0000563
AC:
3
AN:
53330
Middle Eastern (MID)
AF:
0.000173
AC:
1
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000351
AC:
39
AN:
1112006
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.479
Heterozygous variant carriers
0
4
8
12
16
20
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
AF:
0.0000526
AC:
8
AN:
152134
Hom.:
0
Cov.:
32
AF XY:
0.0000538
AC XY:
4
AN XY:
74320
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41426
American (AMR)
AF:
0.000196
AC:
3
AN:
15276
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68014
Other (OTH)
AF:
0.000958
AC:
2
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.0000957
Hom.:
0
Bravo
AF:
0.0000567
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:6Uncertain:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Autosomal recessive congenital ichthyosis 1 Pathogenic:4Uncertain:1
Mar 13, 2024
Baylor Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 01, 2009
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Feb 20, 2020
Natera, Inc.
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Feb 27, 2018
Counsyl
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

May 06, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Pathogenic:2
-
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

The TGM1 p.R126C variant was identified as a compound heterozygous variant in 3 of 164 proband chromosomes (frequency: 0.0183) from individuals with Autosomal Recessive Congenital Ichthyosis (Herman_2009_PMID:19241467; Borsk√°_2019_PMID:31046801; Oji_2006_PMID:16968736). The variant was identified in dbSNP (ID: rs397514524) and ClinVar (classified as uncertain significance by Counsyl for Autosomal recessive congenital ichthyosis 1). The variant was identified in control databases in 7 of 251168 chromosomes at a frequency of 0.00002787 (Genome Aggregation Database March 6, 2019, v2.1.1). The variant was observed in the following populations: Other in 1 of 6126 chromosomes (freq: 0.000163), African in 1 of 16206 chromosomes (freq: 0.000062), European (Finnish) in 1 of 21594 chromosomes (freq: 0.000046) and European (non-Finnish) in 4 of 113590 chromosomes (freq: 0.000035), but was not observed in the Latino, Ashkenazi Jewish, East Asian, or South Asian populations. The p.R126 residue is conserved in mammals but not in more distantly related organisms, and computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) suggest that the variant may impact the protein. The variant occurs outside of the splicing consensus sequence and in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) do not predict a difference in splicing. This variant showed reduced expression and reduced relative TGase-1 protein activity compared to the wild-type (Oji_2006_PMID:16968736; Aufenvenne_2009_PMID:19212342). In summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time although we would lean towards a more pathogenic role for this variant. This variant is classified as likely pathogenic. -

Feb 03, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 126 of the TGM1 protein (p.Arg126Cys). This variant is present in population databases (rs397514524, gnomAD 0.007%). This missense change has been observed in individuals with congenital ichthyosis (PMID: 16968736, 19241467). ClinVar contains an entry for this variant (Variation ID: 39528). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt TGM1 protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects TGM1 function (PMID: 19212342). This variant disrupts the p.Arg126 amino acid residue in TGM1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 19241467, 22437313, 31046801, 31168818). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.37
BayesDel_addAF
Pathogenic
0.30
D
BayesDel_noAF
Pathogenic
0.38
CADD
Pathogenic
26
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.78
D;T
Eigen
Uncertain
0.53
Eigen_PC
Uncertain
0.46
FATHMM_MKL
Uncertain
0.92
D
M_CAP
Pathogenic
0.47
D
MetaRNN
Pathogenic
0.91
D;D
MetaSVM
Uncertain
0.60
D
MutationAssessor
Benign
1.8
L;.
PhyloP100
1.5
PrimateAI
Benign
0.41
T
PROVEAN
Pathogenic
-5.3
D;D
REVEL
Pathogenic
0.82
Sift
Pathogenic
0.0
D;D
Sift4G
Uncertain
0.0020
D;D
Polyphen
1.0
D;.
Vest4
0.64
MVP
0.98
MPC
1.1
ClinPred
0.91
D
GERP RS
5.3
Varity_R
0.66
gMVP
0.73
Mutation Taster
=12/88
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: rs397514524; hg19: chr14-24731033; COSMIC: COSV52864976; COSMIC: COSV52864976; API