NM_001098.3:c.2050C>T

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 0P and 0B.

The NM_001098.3(ACO2):​c.2050C>T​(p.Arg684Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000775 in 1,613,380 control chromosomes in the GnomAD database, including 1 homozygotes. 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. R684Q) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000080 ( 1 hom. )

Consequence

ACO2
NM_001098.3 missense

Scores

5
9
5

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts P:1U:4

Conservation

PhyloP100: 3.06

Publications

4 publications found
Variant links:
Genes affected
ACO2 (HGNC:118): (aconitase 2) The protein encoded by this gene belongs to the aconitase/IPM isomerase family. It is an enzyme that catalyzes the interconversion of citrate to isocitrate via cis-aconitate in the second step of the TCA cycle. This protein is encoded in the nucleus and functions in the mitochondrion. It was found to be one of the mitochondrial matrix proteins that are preferentially degraded by the serine protease 15(PRSS15), also known as Lon protease, after oxidative modification. [provided by RefSeq, Jul 2008]
POLR3H (HGNC:30349): (RNA polymerase III subunit H) Enables DNA-directed 5'-3' RNA polymerase activity. Involved in transcription by RNA polymerase III. Located in centrosome and nucleoplasm. Part of RNA polymerase III complex. [provided by Alliance of Genome Resources, Apr 2022]
POLR3H Gene-Disease associations (from GenCC):
  • 46 XX gonadal dysgenesis
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ACO2NM_001098.3 linkc.2050C>T p.Arg684Trp missense_variant Exon 16 of 18 ENST00000216254.9 NP_001089.1 Q99798
POLR3HNM_001018050.4 linkc.*1899G>A 3_prime_UTR_variant Exon 6 of 6 ENST00000355209.9 NP_001018060.1 Q9Y535-1A0A024R1P3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ACO2ENST00000216254.9 linkc.2050C>T p.Arg684Trp missense_variant Exon 16 of 18 1 NM_001098.3 ENSP00000216254.4 Q99798
POLR3HENST00000355209.9 linkc.*1899G>A 3_prime_UTR_variant Exon 6 of 6 1 NM_001018050.4 ENSP00000347345.4 Q9Y535-1

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152208
Hom.:
0
Cov.:
33
show subpopulations
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:
0.000118
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000722
AC:
18
AN:
249332
AF XY:
0.0000667
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000929
Gnomad NFE exome
AF:
0.000143
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000801
AC:
117
AN:
1461172
Hom.:
1
Cov.:
31
AF XY:
0.0000908
AC XY:
66
AN XY:
726904
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33470
American (AMR)
AF:
0.00
AC:
0
AN:
44680
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26102
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.0000348
AC:
3
AN:
86210
European-Finnish (FIN)
AF:
0.0000188
AC:
1
AN:
53314
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5462
European-Non Finnish (NFE)
AF:
0.000101
AC:
112
AN:
1111888
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60348
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.469
Heterozygous variant carriers
0
9
18
28
37
46
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
4
8
12
16
20
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000526
AC:
8
AN:
152208
Hom.:
0
Cov.:
33
AF XY:
0.0000403
AC XY:
3
AN XY:
74356
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41454
American (AMR)
AF:
0.00
AC:
0
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5200
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000118
AC:
8
AN:
68030
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.469
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000451
Hom.:
0
Bravo
AF:
0.0000340
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000259
AC:
1
ExAC
AF:
0.0000659
AC:
8
EpiCase
AF:
0.0000545
EpiControl
AF:
0.000178

ClinVar

Significance: Uncertain significance
Submissions summary: Pathogenic:1Uncertain:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Infantile cerebellar-retinal degeneration Pathogenic:1Uncertain:1
Sep 16, 2020
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Jul 11, 2018
Mayo Clinic Laboratories, Mayo Clinic
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:2
Nov 20, 2024
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Identified by whole exome sequencing in two siblings who also harbored a second missense variant on the opposite allele (in trans). Both siblings with ataxia, mild developmental delay, behavioral issues (PMID: 32519519); Identified with a second missense variant in two siblings with moderate global developmental delay, seizures, hypotonia, ataxia and cerebellar atrophy (PMID: 30689204); Functional studies demonstrate this variant reduces aconitase activity to approximately 70% of wildtype (PMID: 30689204); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 35368710, 34354088, 33144682, 32519519, 30689204) -

May 09, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 684 of the ACO2 protein (p.Arg684Trp). This variant is present in population databases (rs768950391, gnomAD 0.01%). This missense change has been observed in individual(s) with clinical features of ACO2-related conditions (PMID: 30689204, 32519519). ClinVar contains an entry for this variant (Variation ID: 562210). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on ACO2 protein function. Experimental studies have shown that this missense change affects ACO2 function (PMID: 30689204). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Infantile cerebellar-retinal degeneration;C4225384:Optic atrophy 9 Uncertain:1
Mar 01, 2022
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.41
BayesDel_addAF
Uncertain
0.044
T
BayesDel_noAF
Uncertain
0.080
CADD
Pathogenic
27
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.81
D;.
Eigen
Uncertain
0.48
Eigen_PC
Uncertain
0.49
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Uncertain
0.94
D;D
M_CAP
Benign
0.083
D
MetaRNN
Uncertain
0.65
D;D
MetaSVM
Benign
-0.39
T
MutationAssessor
Pathogenic
4.2
H;.
PhyloP100
3.1
PrimateAI
Pathogenic
0.88
D
PROVEAN
Pathogenic
-4.5
D;D
REVEL
Benign
0.28
Sift
Benign
0.11
T;T
Sift4G
Uncertain
0.028
D;D
Polyphen
0.57
P;B
Vest4
0.84
MVP
0.76
MPC
1.6
ClinPred
0.96
D
GERP RS
5.2
Varity_R
0.52
gMVP
0.85
Mutation Taster
=7/93
disease causing

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

Other links and lift over

dbSNP: rs768950391; hg19: chr22-41923388; API