Genetic Variant C19orf12:p.Ala56LeufsTer6 (chr19-29702971-GC-G) – ACMG Classification: Pathogenic (14 pts)

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PVS1_StrongPM2PP5_Very_Strong

The NM_031448.6(C19orf12):c.166delG(p.Ala56LeufsTer6) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000496 in 1,613,440 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

C19orf12
NM_031448.6 frameshift

Scores

Not classified

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4

Conservation

PhyloP100: 2.30

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]

C19orf12 links:

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ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 14 ACMG points.

PVS1

Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 13 pathogenic variants in the truncated region.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 19-29702971-GC-G is Pathogenic according to our data. Variant chr19-29702971-GC-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1344261.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
C19orf12	NM_031448.6 link	c.166delG	p.Ala56LeufsTer6	frameshift_variant	Exon 3 of 3	ENST00000323670.14	NP_113636.2	Q9NSK7-4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
C19orf12	ENST00000323670.14 link	c.166delG	p.Ala56LeufsTer6	frameshift_variant	Exon 3 of 3	2	NM_031448.6	ENSP00000313332.9		Q9NSK7-4

Frequencies

GnomAD3 genomes

AF:

0.00000659

AC:

AN:

151632

Hom.:

Cov.:

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:

0.000208

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000121

AC:

AN:

248898

Hom.:

AF XY:

0.0000223

AC XY:

AN XY:

134812

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:

0.0000980

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000479

AC:

AN:

1461808

Hom.:

Cov.:

AF XY:

0.00000963

AC XY:

AN XY:

727212

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.0000383

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000696

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000659

AC:

AN:

151632

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74036

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000208

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Hereditary spastic paraplegia 43

Pathogenic:1

Jan 07, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Ala67Leufs*6) in the C19orf12 gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 86 amino acid(s) of the C19orf12 protein. This variant is present in population databases (no rsID available, gnomAD 0.01%). This premature translational stop signal has been observed in individuals with clinical features of autosomal recessive neurodegeneration with brain iron accumulation (PMID: 23269600, 31105013). It has also been observed to segregate with disease in related individuals. This variant is also known as c.194delG. ClinVar contains an entry for this variant (Variation ID: 1344261). For these reasons, this variant has been classified as Pathogenic. -

Neurodegeneration with brain iron accumulation 4

Pathogenic:1

Jun 01, 2022

Solve-RD Consortium

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: provider interpretation

Variant confirmed as disease-causing by referring clinical team -

Hereditary spastic paraplegia

Pathogenic:1

Nov 01, 2017

Genome Diagnostics Laboratory, The Hospital for Sick Children

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided

Pathogenic:1

May 13, 2023

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Frameshift variant predicted to result in protein truncation, as the last 86 amino acids are replaced with 5 different amino acids, and other loss-of-function variants have been reported downstream in HGMD; Not observed at significant frequency in large population cohorts (gnomAD); Also known as c.194delG; This variant is associated with the following publications: (PMID: 23269600, 31087512, 31105013, 31804703, 25962551) -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

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

LitVar

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

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over