9-32419143-T-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_002197.3(ACO1):c.764T>G(p.Val255Gly) 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 pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: ACO1 NM_002197.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.51

Genes affected

ACO1 (HGNC:117): (aconitase 1) The protein encoded by this gene is a bifunctional, cytosolic protein that functions as an essential enzyme in the TCA cycle and interacts with mRNA to control the levels of iron inside cells. When cellular iron levels are high, this protein binds to a 4Fe-4S cluster and functions as an aconitase. Aconitases are iron-sulfur proteins that function to catalyze the conversion of citrate to isocitrate. When cellular iron levels are low, the protein binds to iron-responsive elements (IREs), which are stem-loop structures found in the 5' UTR of ferritin mRNA, and in the 3' UTR of transferrin receptor mRNA. When the protein binds to IRE, it results in repression of translation of ferritin mRNA, and inhibition of degradation of the otherwise rapidly degraded transferrin receptor mRNA. The encoded protein has been identified as a moonlighting protein based on its ability to perform mechanistically distinct functions. Alternative splicing results in multiple transcript variants [provided by RefSeq, Jan 2014]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.895

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ACO1	NM_002197.3	c.764T>G	p.Val255Gly	missense_variant	7/21	ENST00000309951.8
ACO1	NM_001278352.2	c.764T>G	p.Val255Gly	missense_variant	8/22
ACO1	NM_001362840.2	c.764T>G	p.Val255Gly	missense_variant	8/22
ACO1	XM_047423430.1	c.788T>G	p.Val263Gly	missense_variant	7/21

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ACO1	ENST00000309951.8	c.764T>G	p.Val255Gly	missense_variant	7/21	1	NM_002197.3	P1
ACO1	ENST00000379923.5	c.764T>G	p.Val255Gly	missense_variant	8/22	5		P1
ACO1	ENST00000541043.5	c.764T>G	p.Val255Gly	missense_variant	8/22	5		P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 13, 2023

The c.764T>G (p.V255G) alteration is located in exon 7 (coding exon 6) of the ACO1 gene. This alteration results from a T to G substitution at nucleotide position 764, causing the valine (V) at amino acid position 255 to be replaced by a glycine (G). 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	Uncertain	0.44
BayesDel_addAF	Pathogenic	0.26	D
BayesDel_noAF	Pathogenic	0.14
Cadd	Pathogenic	27
Dann	Uncertain	1.0
DEOGEN2	Pathogenic	0.85	D;D;D
Eigen	Pathogenic	0.81
Eigen_PC	Pathogenic	0.75
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Benign	0.84	T;.;.
M_CAP	Benign	0.055	D
MetaRNN	Pathogenic	0.89	D;D;D
MetaSVM	Benign	-0.40	T
MutationAssessor	Pathogenic	4.1	H;H;H
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Benign	0.47	T
REVEL	Uncertain	0.51
Sift4G	Pathogenic	0.0	D;D;D
Polyphen		0.96	D;D;D
Vest4		0.67
MutPred		0.81		Loss of stability (P = 0.0068);Loss of stability (P = 0.0068);Loss of stability (P = 0.0068);
MVP		0.64
MPC		0.87
ClinPred		1.0	D
GERP RS		5.6
Varity_R		0.97
gMVP		0.97

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

LitVar

Other links and lift over

dbSNP: rs1587534424; hg19: chr9-32419141;