12-6934564-A-C

Position:

• chr12-6934564-A-C

Variant summary

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

The NM_001940.4(ATN1):​c.265A>C​(p.Lys89Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: ATN1 NM_001940.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.41

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 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ATN1	NM_001940.4	c.265A>C	p.Lys89Gln	missense_variant	4/10	ENST00000396684.3
ATN1	NM_001007026.2	c.265A>C	p.Lys89Gln	missense_variant	4/10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ATN1	ENST00000396684.3	c.265A>C	p.Lys89Gln	missense_variant	4/10	1	NM_001940.4	P1
ATN1	ENST00000356654.8	c.265A>C	p.Lys89Gln	missense_variant	4/10	1		P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jun 11, 2024

The c.265A>C (p.K89Q) alteration is located in exon 4 (coding exon 3) of the ATN1 gene. This alteration results from a A to C substitution at nucleotide position 265, causing the lysine (K) at amino acid position 89 to be replaced by a glutamine (Q). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.76
BayesDel_addAF	Benign	-0.095	T
BayesDel_noAF	Benign	-0.37
CADD	Pathogenic	27
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.50	D;D
Eigen	Uncertain	0.52
Eigen_PC	Uncertain	0.50
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Benign	0.82	.;T
M_CAP	Benign	0.011	T
MetaRNN	Uncertain	0.48	T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	1.9	L;L
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Pathogenic	0.80	D
PROVEAN	Benign	-2.2	N;N
REVEL	Benign	0.28
Sift	Uncertain	0.0020	D;D
Sift4G	Uncertain	0.021	D;D
Polyphen		1.0	D;D
Vest4		0.36
MutPred		0.37		Loss of methylation at K89 (P = 0.0013);Loss of methylation at K89 (P = 0.0013);
MVP		0.52
MPC		0.44
ClinPred		0.97	D
GERP RS		5.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.36
gMVP		0.35

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: rs1461513753; hg19: chr12-7043727;