rs760429286

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_000359.3(TGM1):​c.232C>T​(p.Arg78*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000062 in 1,613,482 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 Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

TGM1
NM_000359.3 stop_gained

Scores

1
1
5

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:9

Conservation

PhyloP100: 0.736
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 14-24262121-G-A is Pathogenic according to our data. Variant chr14-24262121-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 449511.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr14-24262121-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TGM1NM_000359.3 linkc.232C>T p.Arg78* stop_gained Exon 2 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.232C>T p.Arg78* stop_gained Exon 2 of 15 1 NM_000359.3 ENSP00000206765.6 P22735-1

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152190
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000724
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
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:
0.00
GnomAD3 exomes
AF:
0.0000120
AC:
3
AN:
250334
Hom.:
0
AF XY:
0.00000738
AC XY:
1
AN XY:
135562
show subpopulations
Gnomad AFR exome
AF:
0.0000618
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000462
Gnomad NFE exome
AF:
0.00000887
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000479
AC:
7
AN:
1461292
Hom.:
0
Cov.:
33
AF XY:
0.00000275
AC XY:
2
AN XY:
726944
show subpopulations
Gnomad4 AFR exome
AF:
0.0000597
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.0000189
Gnomad4 NFE exome
AF:
0.00000270
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152190
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74344
show subpopulations
Gnomad4 AFR
AF:
0.0000724
Gnomad4 AMR
AF:
0.00
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:
0.00
Alfa
AF:
0.0000324
Hom.:
0
Bravo
AF:
0.0000264
ExAC
AF:
0.0000165
AC:
2

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:9
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Autosomal recessive congenital ichthyosis 1 Pathogenic:5
Sep 16, 2020
Natera, Inc.
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

-
Genome-Nilou Lab
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Jan 03, 2022
3billion
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Stop-gained (nonsense): predicted to result in a loss or disruption of normal protein function through nonsense-mediated decay (NMD) or protein truncation. Multiple pathogenic variants are reported downstream of the variant (PVS1_VS).The variant has been reported at least twice as pathogenic/likely pathogenic with clinical assertions and evidence for the classification (ClinVar ID: VCV000449511, PMID:7581379, 3billion dataset). It is observed at an extremely low frequency in the gnomAD v2.1.1 dataset (total allele frequency: 0.000012, PM2_M). The variant has been reported to be in trans as homozygous in at least one similarly affected unrelated individual (3billion dataset, PM3_P). Therefore, this variant is classified as pathogenic according to the recommendation of ACMG/AMP guideline. -

Aug 22, 2023
Baylor Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Feb 16, 2017
Counsyl
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

not provided Pathogenic:2
May 15, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Arg78*) in the TGM1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in TGM1 are known to be pathogenic (PMID: 18948357, 19241467). For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 449511). This premature translational stop signal has been observed in individual(s) with lamellar ichthyosis (PMID: 7581379). It has also been observed to segregate with disease in related individuals. This variant is present in population databases (rs760429286, gnomAD 0.007%). -

Oct 12, 2023
GeneDx
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; This variant is associated with the following publications: (PMID: 7581379, 23895935) -

Lamellar ichthyosis Pathogenic:1
Sep 25, 2019
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: TGM1 c.232C>T (p.Arg78X) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay. The variant allele was found at a frequency of 1.2e-05 in 250334 control chromosomes. c.232C>T has been reported in the literature in individuals affected with Lamellar ichthyosis, including two affected brothers from the same family (Parmentier_1995, Sugiura_2013). These data indicate that the variant is likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

TGM1-related disorder Pathogenic:1
Feb 27, 2024
PreventionGenetics, part of Exact Sciences
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

The TGM1 c.232C>T variant is predicted to result in premature protein termination (p.Arg78*). This variant has been reported in the homozygous state in several individuals with ichthyosis (Parmentier et al. 1995. PubMed ID: 7581379; Khan et al. 2023. PubMed ID: 36789964); and, it has been observed to co-segregate with disease in the affected family members (same studies). It has also been reported in the compound heterozygous state in a mildly affected patient along with a second TGM1 missense variant of uncertain significance (Sugiura et al. 2013. PubMed ID: 23895935). This variant is reported in 0.0062% of alleles in individuals of African descent in gnomAD. Nonsense variants in TGM1 are expected to be pathogenic. This variant is interpreted as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.50
D
BayesDel_noAF
Uncertain
-0.040
CADD
Pathogenic
35
DANN
Benign
0.97
Eigen
Benign
0.010
Eigen_PC
Benign
-0.32
FATHMM_MKL
Benign
0.38
N
Vest4
0.60
GERP RS
1.2

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs760429286; hg19: chr14-24731327; API