rs121918726

Positions:

• chr14-24258658-C-A
• chr14-24258658-C-T

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PM1 PM2 PM5 PP3_Strong PP5_Moderate

The ENST00000206765.11(TGM1):​c.1175G>T​(p.Gly392Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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. G392D) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: TGM1 ENST00000206765.11 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 7.65

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]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 4 uncertain in ENST00000206765.11
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr14-24258658-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 12493.Status of the report is no_assertion_criteria_provided, 0 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.993
• PP5: Variant 14-24258658-C-A is Pathogenic according to our data. Variant chr14-24258658-C-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1491016.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TGM1	NM_000359.3	c.1175G>T	p.Gly392Val	missense_variant	8/15	ENST00000206765.11	NP_000350.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TGM1	ENST00000206765.11	c.1175G>T	p.Gly392Val	missense_variant	8/15	1	NM_000359.3	ENSP00000206765	P1
TGM1	ENST00000559136.1	c.248G>T	p.Gly83Val	missense_variant	4/7	5		ENSP00000453337
TGM1	ENST00000544573.5	c.-28-270G>T		intron_variant		2		ENSP00000439446

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 36

GnomAD4 genome Cov.: 33

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 22, 2021

In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt TGM1 protein function. This missense change has been observed in individual(s) with congenital ichthyosis (Invitae). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glycine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 392 of the TGM1 protein (p.Gly392Val). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.58	D
BayesDel_noAF	Pathogenic	0.59
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.98	D;D
Eigen	Pathogenic	0.94
Eigen_PC	Pathogenic	0.83
FATHMM_MKL	Pathogenic	0.98	D
M_CAP	Pathogenic	0.54	D
MetaRNN	Pathogenic	0.99	D;D
MetaSVM	Pathogenic	0.98	D
MutationAssessor	Pathogenic	3.7	H;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.79	T
PROVEAN	Pathogenic	-8.8	D;D
REVEL	Pathogenic	0.99
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;.
Polyphen		1.0	D;.
Vest4		0.98
MutPred		0.97		Loss of methylation at R389 (P = 0.0774);.;
MVP		0.99
MPC		1.0
ClinPred		1.0	D
GERP RS		4.5
Varity_R		0.97
gMVP		0.97

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr14-24727864;