rs1555890974

Positions:

• chr22-41527918-CAG-C

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_001098.3(ACO2):​c.2105_2106delAG​(p.Gln702fs) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,870 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: ACO2 NM_001098.3 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 8.43

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]

ACO2 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 22-41527918-CAG-C is Pathogenic according to our data. Variant chr22-41527918-CAG-C is described in ClinVar as [Pathogenic]. Clinvar id is 520987.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
ACO2	NM_001098.3	c.2105_2106delAG	p.Gln702fs	frameshift_variant	17/18	ENST00000216254.9	NP_001089.1
POLR3H	NM_001018050.4	c.*1363_*1364delCT		3_prime_UTR_variant	6/6	ENST00000355209.9	NP_001018060.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ACO2	ENST00000216254.9	c.2105_2106delAG	p.Gln702fs	frameshift_variant	17/18	1	NM_001098.3	ENSP00000216254.4
POLR3H	ENST00000355209.9	c.*1363_*1364delCT		3_prime_UTR_variant	6/6	1	NM_001018050.4	ENSP00000347345.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461870 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 727244

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Inborn genetic diseases Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 24, 2016

- -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 03, 2023

This sequence change creates a premature translational stop signal (p.Gln702Argfs*9) in the ACO2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in ACO2 are known to be pathogenic (PMID: 30689204, 32519519). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with ACO2-related conditions. ClinVar contains an entry for this variant (Variation ID: 520987). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs1555890974; hg19: chr22-41923922;