14-24260528-G-A

Variant names:

• chr14-24260528-G-A
• rs972054392
• NM_000359.3:c.679C>T

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000359.3(TGM1):​c.679C>T​(p.Gln227*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000821 in 1,461,886 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 (★★). Synonymous variant affecting the same amino acid position (i.e. Q227Q) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000082 (0 hom.)
• Consequence: TGM1 NM_000359.3 stop_gained
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 2.67
• Publications: 1 publications found

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

ACMG classification

Our verdict: Pathogenic. The variant received 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 14-24260528-G-A is Pathogenic according to our data. Variant chr14-24260528-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 555912.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000359.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TGM1	NM_000359.3	MANE Select	c.679C>T	p.Gln227*	stop_gained	Exon 4 of 15	NP_000350.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TGM1	ENST00000206765.11	TSL:1 MANE Select	c.679C>T	p.Gln227*	stop_gained	Exon 4 of 15	ENSP00000206765.6
	TGM1	ENST00000544573.5	TSL:2	c.-29+1599C>T		intron	N/A	ENSP00000439446.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000821 AC: 12 AN: 1461886 Hom.: 0 Cov.: 32 AF XY: 0.0000124 AC XY: 9 AN XY: 727242

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: 53416

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000989 AC: 11 AN: 1112010

Other (OTH) AF: 0.0000166 AC: 1 AN: 60394

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Autosomal recessive congenital ichthyosis 1 Pathogenic:3

Oct 14, 2023

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Genome-Nilou Lab

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Jan 03, 2018

Counsyl

Significance: Likely pathogenic

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.

not provided Pathogenic:1

Feb 09, 2024

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.Gln227*) 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). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with TGM1-related conditions (PMID: 18948357, 31168818). ClinVar contains an entry for this variant (Variation ID: 555912). For these reasons, this variant has been classified as Pathogenic.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.30
CADD	Pathogenic	36
DANN	Uncertain	1.0
Eigen	Uncertain	0.26
Eigen_PC	Benign	-0.0082
FATHMM_MKL	Benign	0.38	N
PhyloP100		2.7
Vest4		0.75
GERP RS		5.1
PromoterAI		-0.014	Neutral
Mutation Taster		=7/193	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs972054392; hg19: chr14-24729734;