14-24260528-G-C

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 5P and 2B. PM1PM2PP2BP4_Moderate

The NM_000359.3(TGM1):​c.679C>G​(p.Gln227Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,886 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. Q227Q) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

TGM1
NM_000359.3 missense

Scores

1
16

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 2.67

Publications

0 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: Uncertain_significance. The variant received 3 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 5 uncertain in NM_000359.3
PM2
Very rare variant in population databases, with high coverage;
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.
BP4
Computational evidence support a benign effect (MetaRNN=0.19011703).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TGM1NM_000359.3 linkc.679C>G p.Gln227Glu missense_variant Exon 4 of 15 ENST00000206765.11 NP_000350.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TGM1ENST00000206765.11 linkc.679C>G p.Gln227Glu missense_variant Exon 4 of 15 1 NM_000359.3 ENSP00000206765.6
TGM1ENST00000544573.5 linkc.-29+1599C>G intron_variant Intron 2 of 8 2 ENSP00000439446.1

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461886
Hom.:
0
Cov.:
32
AF XY:
0.00000138
AC XY:
1
AN XY:
727242
show subpopulations
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:
8.99e-7
AC:
1
AN:
1112010
Other (OTH)
AF:
0.00
AC:
0
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
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
Cov.:
33

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not specified Uncertain:1
Aug 22, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: TGM1 c.679C>G (p.Gln227Glu) results in a conservative amino acid change in the encoded protein sequence. Four of four in-silico tools predict a benign effect of the variant on protein function. The variant was absent in 251484 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.679C>G in individuals affected with Lamellar Ichthyosis and no experimental evidence demonstrating its impact on protein function have been reported. No submitters have cited clinical-significance assessments for this variant to ClinVar. Based on the evidence outlined above, the variant was classified as uncertain significance.

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.11
BayesDel_addAF
Benign
-0.099
T
BayesDel_noAF
Benign
-0.38
CADD
Benign
15
DANN
Benign
0.61
DEOGEN2
Benign
0.32
T
Eigen
Benign
-0.97
Eigen_PC
Benign
-0.83
FATHMM_MKL
Benign
0.43
N
M_CAP
Benign
0.028
D
MetaRNN
Benign
0.19
T
MetaSVM
Benign
-0.91
T
MutationAssessor
Benign
0.0
N
PhyloP100
2.7
PrimateAI
Benign
0.25
T
PROVEAN
Benign
-0.19
N
REVEL
Uncertain
0.33
Sift
Benign
0.32
T
Sift4G
Benign
0.79
T
Vest4
0.23
ClinPred
0.12
T
GERP RS
5.1
PromoterAI
-0.010
Neutral
Varity_R
0.14
gMVP
0.58
Mutation Taster
=95/5
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs972054392; hg19: chr14-24729734; API