12-6935734-C-T

Position:

• chr12-6935734-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_001940.4(ATN1):​c.467C>T​(p.Ala156Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000658 in 152,024 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A156G) has been classified as Uncertain significance.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 31)
• Consequence: ATN1 NM_001940.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.49

Genes affected

ATN1 (HGNC:3033): (atrophin 1) Dentatorubral pallidoluysian atrophy (DRPLA) is a rare neurodegenerative disorder characterized by cerebellar ataxia, myoclonic epilepsy, choreoathetosis, and dementia. The disorder is related to the expansion from 7-35 copies to 49-93 copies of a trinucleotide repeat (CAG/CAA) within this gene. The encoded protein includes a serine repeat and a region of alternating acidic and basic amino acids, as well as the variable glutamine repeat. Alternative splicing results in two transcripts variants that encode the same protein. [provided by RefSeq, Jul 2016]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.12042114).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ATN1	NM_001940.4	c.467C>T	p.Ala156Val	missense_variant	5/10	ENST00000396684.3
ATN1	NM_001007026.2	c.467C>T	p.Ala156Val	missense_variant	5/10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ATN1	ENST00000396684.3	c.467C>T	p.Ala156Val	missense_variant	5/10	1	NM_001940.4	P1
ATN1	ENST00000356654.8	c.467C>T	p.Ala156Val	missense_variant	5/10	1		P1

Frequencies

GnomAD3 genomes AF: 0.00000658 AC: 1 AN: 152024 Hom.: 0 Cov.: 31

Gnomad AFR AF: 0.0000242

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: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 37

GnomAD4 genome AF: 0.00000658 AC: 1 AN: 152024 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 74254

Gnomad4 AFR AF: 0.0000242

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Oct 10, 2022

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.11
BayesDel_addAF	Benign	-0.095	T
BayesDel_noAF	Benign	-0.37
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Benign	0.34	T;T
Eigen	Benign	-0.36
Eigen_PC	Benign	-0.19
FATHMM_MKL	Uncertain	0.87	D
LIST_S2	Benign	0.82	.;T
M_CAP	Benign	0.029	D
MetaRNN	Benign	0.12	T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.34	N;N
MutationTaster	Benign	0.99	N;N;N
PrimateAI	Uncertain	0.67	T
PROVEAN	Benign	-1.3	N;N
REVEL	Benign	0.095
Sift	Uncertain	0.0030	D;D
Sift4G	Benign	0.18	T;T
Polyphen		0.011	B;B
Vest4		0.39
MutPred		0.32		Gain of catalytic residue at P161 (P = 5e-04);Gain of catalytic residue at P161 (P = 5e-04);
MVP		0.38
MPC		0.41
ClinPred		0.37	T
GERP RS		3.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.17
gMVP		0.18

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: rs1945521873; hg19: chr12-7044897;