20-2394541-C-A

Variant names:

• chr20-2394541-C-A
• rs147548610
• NM_198994.3:c.97C>A

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_198994.3(TGM6):​c.97C>A​(p.Arg33Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,144 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R33C) has been classified as Uncertain significance.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: TGM6 NM_198994.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.463
• Publications: 1 publications found

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]

TGM6 Gene-Disease associations (from GenCC):

• spinocerebellar ataxia type 35

  Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE, LIMITED Submitted by: PanelApp Australia, Orphanet, Ambry Genetics, Illumina, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.98

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_198994.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TGM6	NM_198994.3	MANE Select	c.97C>A	p.Arg33Ser	missense	Exon 2 of 13	NP_945345.2	O95932-1
	TGM6	NM_001254734.2		c.97C>A	p.Arg33Ser	missense	Exon 2 of 12	NP_001241663.1	O95932-2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TGM6	ENST00000202625.7	TSL:1 MANE Select	c.97C>A	p.Arg33Ser	missense	Exon 2 of 13	ENSP00000202625.2	O95932-1
	TGM6	ENST00000381423.1	TSL:1	c.97C>A	p.Arg33Ser	missense	Exon 2 of 12	ENSP00000370831.1	O95932-2
	TGM6	ENST00000477505.1	TSL:5	n.90C>A		non_coding_transcript_exon	Exon 1 of 4

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152144 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 30

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152144 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74316

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 41420

American (AMR) AF: 0.00 AC: 0 AN: 15278

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5188

South Asian (SAS) AF: 0.00 AC: 0 AN: 4822

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10620

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68026

Other (OTH) AF: 0.00 AC: 0 AN: 2092

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.00 Hom.: 0

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.50	D
BayesDel_noAF	Pathogenic	0.48
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.62	D
Eigen	Uncertain	0.55
Eigen_PC	Uncertain	0.41
FATHMM_MKL	Benign	0.39	N
LIST_S2	Pathogenic	0.99	D
M_CAP	Uncertain	0.089	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.9	H
PhyloP100		0.46
PrimateAI	Uncertain	0.59	T
PROVEAN	Pathogenic	-5.5	D
REVEL	Pathogenic	0.89
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.85
MutPred		0.94		Gain of phosphorylation at R33 (P = 0.0613)
MVP		0.90
MPC		0.49
ClinPred		1.0	D
GERP RS		3.5
Varity_R		0.98
gMVP		0.66
Mutation Taster		=64/36	polymorphism

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: rs147548610; hg19: chr20-2375187;