2-231262306-C-A

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PM5

The NM_001352754.2(ARMC9):​c.1027C>A​(p.Arg343Ser) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.00000274 in 1,461,796 control chromosomes in the GnomAD database, with no homozygous occurrence. 3/3 splice prediction tools predict no significant impact on normal splicing. 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. R343C) has been classified as Pathogenic.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

ARMC9
NM_001352754.2 missense, splice_region

Scores

6
10
3
Splicing: ADA: 0.5027
2

Clinical Significance

Uncertain significance criteria provided, single submitter P:3U:1

Conservation

PhyloP100: 3.96
Variant links:
Genes affected
ARMC9 (HGNC:20730): (armadillo repeat containing 9) Predicted to be involved in cilium assembly and positive regulation of smoothened signaling pathway. Located in centriole and ciliary basal body. Implicated in Joubert syndrome 30. [provided by Alliance of Genome Resources, Apr 2022]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr2-231262306-C-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
ARMC9NM_001352754.2 linkuse as main transcriptc.1027C>A p.Arg343Ser missense_variant, splice_region_variant 12/25 ENST00000611582.5 NP_001339683.2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
ARMC9ENST00000611582.5 linkuse as main transcriptc.1027C>A p.Arg343Ser missense_variant, splice_region_variant 12/255 NM_001352754.2 ENSP00000484804 P1Q7Z3E5-1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD3 exomes
AF:
0.00000398
AC:
1
AN:
251460
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135908
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 SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000274
AC:
4
AN:
1461796
Hom.:
0
Cov.:
30
AF XY:
0.00
AC XY:
0
AN XY:
727202
show subpopulations
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:
0.00000360
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
Cov.:
32
Bravo
AF:
0.00000378
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Pathogenic:3Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Joubert syndrome 30 Pathogenic:1Uncertain:1
Uncertain significance, criteria provided, single submittercurationBroad Center for Mendelian Genomics, Broad Institute of MIT and HarvardMar 12, 2024The heterozygous p.Arg343Ser variant in ARMC9 was identified by our study in one individual with congenital fibrosis of the extraocular muscles and Joubert syndrome, via a collaborative study between the Broad Institute's Center for Mendelian Genomics and the Engle lab (https://kirbyneuro.org/EngleLab/). The p.Arg343Ser variant in ARMC9 has been previously reported in two siblings with Joubert syndrome 30 (PMID: 28625504) but has been identified in 0.0009% (1/113742) of European (non-Finnish) chromosomes by the Genome Aggregation Database (gnomAD, http://gnomad.broadinstitute.org; dbSNP ID: rs759799287). Although this variant has been seen in the general population in a heterozygous state, its frequency is low enough to be consistent with a recessive carrier frequency. These two affected individuals were compound heterozygotes that carried a likely pathogenic variant in trans (ClinVar Variation ID: 427933), which increases the likelihood that the p.Arg343Ser variant is pathogenic. This variant has also been reported in ClinVar (Variation ID: 427937) and has been interpreted as pathogenic by OMIM and the UW Hindbrain Malformation Research Program and as likely pathogenic by the University of Washington Center for Mendelian Genomics. One additional likely pathogenic variant, resulting in a different amino acid change at the same position, p.Arg343Cys, has been reported in association with disease in the literature and in ClinVar, slightly supporting that a change at this position may not be tolerated (PMID: 28625504, 31474318, 32552793, 35186037; Variation ID: 427932). Computational prediction tools and conservation analyses do not provide strong support for or against an impact to the protein. In summary, while there is some suspicion for a pathogenic role, the clinical significance of this variant is uncertain. ACMG/AMP Criteria applied: PM2_Supporting, PM3, PM5_Supporting (Richards 2015). -
Pathogenic, no assertion criteria providedliterature onlyOMIMAug 16, 2017- -
ARMC9-related Joubert syndrome Pathogenic:1
Pathogenic, no assertion criteria providedresearchUW Hindbrain Malformation Research Program, University of WashingtonMay 01, 2017- -
Familial aplasia of the vermis Pathogenic:1
Likely pathogenic, no assertion criteria providedresearchUniversity of Washington Center for Mendelian Genomics, University of Washington-- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.99
BayesDel_addAF
Pathogenic
0.27
D
BayesDel_noAF
Pathogenic
0.15
CADD
Pathogenic
30
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.64
.;D;D;.
Eigen
Uncertain
0.57
Eigen_PC
Uncertain
0.50
FATHMM_MKL
Uncertain
0.79
D
LIST_S2
Pathogenic
0.98
D;D;.;D
M_CAP
Benign
0.053
D
MetaRNN
Uncertain
0.56
D;D;D;D
MetaSVM
Benign
-0.71
T
MutationAssessor
Uncertain
2.7
.;M;M;.
MutationTaster
Benign
1.0
D
PrimateAI
Uncertain
0.64
T
PROVEAN
Pathogenic
-4.5
D;.;.;D
REVEL
Uncertain
0.35
Sift
Pathogenic
0.0
D;.;.;D
Sift4G
Uncertain
0.0040
D;D;D;D
Polyphen
1.0
.;D;D;.
Vest4
0.94
MVP
0.54
MPC
0.87
ClinPred
0.99
D
GERP RS
4.1
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.47
gMVP
0.80

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.50
dbscSNV1_RF
Benign
0.69
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

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs759799287; hg19: chr2-232127019; API