19-29702977-C-T

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PM1PM2PM5PP3_StrongPP5_Very_Strong

The NM_031448.6(C19orf12):​c.161G>A​(p.Gly54Glu) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000204 in 1,614,008 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G54V) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000021 ( 0 hom. )

Consequence

C19orf12
NM_031448.6 missense, splice_region

Scores

10
7
1
Splicing: ADA: 0.9984
2

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:6

Conservation

PhyloP100: 7.26
Variant links:
Genes affected
C19orf12 (HGNC:25443): (chromosome 19 open reading frame 12) This gene encodes a small transmembrane protein. Mutations in this gene are a cause of neurodegeneration with brain iron accumulation-4 (NBIA4), but the specific function of the encoded protein is unknown. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Dec 2011]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PM1
In a transmembrane_region Helical (size 20) in uniprot entity CS012_HUMAN there are 10 pathogenic changes around while only 0 benign (100%) in NM_031448.6
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr19-29702977-C-A is described in Lovd as [Pathogenic].
PP3
MetaRNN computational evidence supports a deleterious effect, 0.957
PP5
Variant 19-29702977-C-T is Pathogenic according to our data. Variant chr19-29702977-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 617481.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
C19orf12NM_031448.6 linkuse as main transcriptc.161G>A p.Gly54Glu missense_variant, splice_region_variant 3/3 ENST00000323670.14 NP_113636.2 Q9NSK7-4

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
C19orf12ENST00000323670.14 linkuse as main transcriptc.161G>A p.Gly54Glu missense_variant, splice_region_variant 3/32 NM_031448.6 ENSP00000313332.9 Q9NSK7-4

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152130
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000120
AC:
3
AN:
249090
Hom.:
0
AF XY:
0.00000742
AC XY:
1
AN XY:
134842
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:
0.0000327
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000180
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000212
AC:
31
AN:
1461878
Hom.:
0
Cov.:
37
AF XY:
0.0000206
AC XY:
15
AN XY:
727238
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:
0.0000580
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000234
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152130
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74336
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.0000655
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000151
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:6
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Neurodegeneration with brain iron accumulation 4 Pathogenic:2
Pathogenic, no assertion criteria providedclinical testingAziz Sancar Institute of Experimental Medicine, Istanbul UniversityMar 03, 2018This variant is associated with neurodegeneration with brain iron accumulation (spasticity, dystonia, optic atrophy). -
Pathogenic, criteria provided, single submitterclinical testingVictorian Clinical Genetics Services, Murdoch Childrens Research InstituteMay 21, 2020A homozygous missense variant was identified, NM_001256047.1(C19orf12):c.161G>A in exon 3 of 3 of the C19orf12 gene. (NB: this variant is non-coding in alternative transcripts). This substitution is predicted to create a moderate amino acid change from a glycine to a glutamic acid at position 54 of the protein; NP_001242976.1(C19orf12):p.(Gly54Glu). The glycine at this position has very high conservation (100 vertebrates, UCSC), and is not situated in a known functional domain (NCBI, PDB). In silico software predicts this variant to be damaging (PolyPhen2, SIFT, CADD, Mutation Taster). The variant is present in the gnomAD population database at a frequency of 0.001% (3 heterozygotes, 0 homozygotes). This variant has been previously reported as pathogenic in several patients (ClinVar, Hartig, MB. et al. (2011), Hogarth, P. et al. (2013)). A different variant in the same codon resulting in a change to a valine has also been reported as pathogenic (ClinVar, Gregory, A. et al. (2019)). Based on information available at the time of curation, this variant has been classified as PATHOGENIC. Legend: (P) - Pathogenic, (N) - Neutral, (B) - Benign -
not provided Pathogenic:2
Pathogenic, criteria provided, single submitterclinical testingRevvity Omics, RevvityMar 19, 2020- -
Likely pathogenic, criteria provided, single submitterclinical testingGeneDxSep 16, 2020Not observed at a significant frequency in large population cohorts (Lek et al., 2016); In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; This variant is associated with the following publications: (PMID: 23269600, 31087512, 21981780, 24098554, 26136767, 22584950, 31804703) -
Hereditary spastic paraplegia 43 Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJul 07, 2023This sequence change replaces glycine, which is neutral and non-polar, with glutamic acid, which is acidic and polar, at codon 65 of the C19orf12 protein (p.Gly65Glu). For these reasons, this variant has been classified as Pathogenic. An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. ClinVar contains an entry for this variant (Variation ID: 617481). This missense change has been observed in individual(s) with neurodegeneration with brain iron accumulation (NBIA) (PMID: 21981780, 23269600, 31087512). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. This variant is present in population databases (rs752450983, gnomAD 0.003%). -
Neurodegeneration with brain iron accumulation Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpMar 20, 2023Variant summary: C19orf12 c.161G>A/p.Gly54Glu (legacy name: c.194G>A/p.Gly65Glu) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. In addition the variant is located to the first nucleotide of exon 3, and therefore can affect splicing. Several computational tools predict a significant impact on normal splicing: four predict the variant mildly weakens a 3' acceptor site, while one predicts the variant creates a novel 3' acceptor site, two nucleotides downstream from the original splice-site. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 1.2e-05 in 249090 control chromosomes (gnomAD). c.161G>A has been reported in the literature in multiple homozygous and compound heterozygous individuals affected with Neurodegeneration with Brain Iron Accumulation (or with symptoms consistent with this disease phenotype) (e.g. Hartig_2011, Gregory_2019, Akcakaya_2019, Wan_2021). These data indicate that the variant is very likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Four clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as pathogenic (n=3) / likely pathogenic (n=1). Based on the evidence outlined above, the variant was classified as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.96
BayesDel_addAF
Pathogenic
0.38
D
BayesDel_noAF
Pathogenic
0.41
CADD
Pathogenic
32
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.49
.;.;.;T;T
Eigen
Pathogenic
0.70
Eigen_PC
Uncertain
0.60
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.89
D;.;D;D;D
M_CAP
Uncertain
0.21
D
MetaRNN
Pathogenic
0.96
D;D;D;D;D
MetaSVM
Uncertain
0.70
D
MutationAssessor
Pathogenic
3.3
.;.;.;M;.
PROVEAN
Pathogenic
-7.3
.;D;.;D;.
REVEL
Pathogenic
0.90
Sift
Pathogenic
0.0
.;D;.;D;.
Sift4G
Uncertain
0.0030
D;D;D;D;.
Vest4
0.91
MutPred
0.82
Gain of solvent accessibility (P = 0.0411);Gain of solvent accessibility (P = 0.0411);Gain of solvent accessibility (P = 0.0411);.;Gain of solvent accessibility (P = 0.0411);
MVP
0.77
MPC
1.3
ClinPred
0.99
D
GERP RS
4.9
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.8
Varity_R
0.95
gMVP
0.99

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.88
SpliceAI score (max)
0.14
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: rs752450983; hg19: chr19-30193884; API