20-2394520-C-T

Position:

• chr20-2394520-C-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_198994.3(TGM6):​c.76C>T​(p.Pro26Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: TGM6 NM_198994.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:2
• Conservation: PhyloP100: -0.497

Genes affected

TGM6 (HGNC:16255): (transglutaminase 6) The protein encoded by this gene belongs to the transglutaminase superfamily. It catalyzes the cross-linking of proteins and the conjugation of polyamines to proteins. Mutations in this gene are associated with spinocerebellar ataxia type 35 (SCA35). Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Dec 2011]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.04316601).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TGM6	NM_198994.3	c.76C>T	p.Pro26Ser	missense_variant	2/13	ENST00000202625.7	NP_945345.2
TGM6	NM_001254734.2	c.76C>T	p.Pro26Ser	missense_variant	2/12		NP_001241663.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TGM6	ENST00000202625.7	c.76C>T	p.Pro26Ser	missense_variant	2/13	1	NM_198994.3	ENSP00000202625	P1
TGM6	ENST00000381423.1	c.76C>T	p.Pro26Ser	missense_variant	2/12	1		ENSP00000370831
TGM6	ENST00000477505.1	n.69C>T		non_coding_transcript_exon_variant	1/4	5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, single submitter

Submissions by phenotype

Rigidity;C0242422:Parkinsonian disorder;C0332615:Myopathic facies;C3489733:Oculomotor apraxia;C4024962:Axial muscle stiffness Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Centre for Mendelian Genomics, University Medical Centre Ljubljana

Jan 01, 2017

- -

Spinocerebellar ataxia type 35 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Centre for Mendelian Genomics, University Medical Centre Ljubljana

May 24, 2019

This variant was classified as: Uncertain significance. The available evidence on this variant's pathogenicity is insufficient or conflicting. The following ACMG criteria were applied in classifying this variant: PM2,BP4. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.072
BayesDel_addAF	Benign	-0.024	T
BayesDel_noAF	Benign	-0.27
CADD	Benign	6.9
DANN	Benign	0.43
DEOGEN2	Benign	0.062	T;.
Eigen	Benign	-0.79
Eigen_PC	Benign	-0.64
FATHMM_MKL	Benign	0.087	N
LIST_S2	Benign	0.30	T;T
M_CAP	Benign	0.0070	T
MetaRNN	Benign	0.043	T;T
MetaSVM	Benign	-0.91	T
MutationAssessor	Benign	0.50	N;N
MutationTaster	Benign	1.0	N;N
PrimateAI	Benign	0.33	T
PROVEAN	Benign	-0.14	N;N
REVEL	Uncertain	0.40
Sift	Benign	1.0	T;T
Sift4G	Benign	1.0	T;T
Polyphen		0.0030	B;B
Vest4		0.13
MutPred		0.38		Loss of catalytic residue at P26 (P = 0.003);Loss of catalytic residue at P26 (P = 0.003);
MVP		0.42
MPC		0.086
ClinPred		0.046	T
GERP RS		3.5
Varity_R		0.060
gMVP		0.079

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

Other links and lift over

dbSNP: rs766248910; hg19: chr20-2375166;