12-4517178-CTG-C

Position:

• chr12-4517178-CTG-C

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_020374.4(C12orf4):​c.1043_1044delCA​(p.Thr348fs) variant causes a frameshift change. The variant allele was found at a frequency of 0.00000287 in 1,394,198 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: 0.0000029 (0 hom.)
• Consequence: C12orf4 NM_020374.4 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 6.47

Genes affected

C12orf4 (HGNC:1184): (FERRY endosomal RAB5 effector complex subunit 3) This gene is highly conserved from nematodes to humans. In rat, the orthologous gene encodes a cytoplasmic protein that is involved in mast cell degranulation. The human gene has been implicated in autosomal recessive intellectual disability. [provided by RefSeq, Sep 2016]

C12orf4 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 12 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 12-4517178-CTG-C is Pathogenic according to our data. Variant chr12-4517178-CTG-C is described in ClinVar as [Pathogenic]. Clinvar id is 3254961.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
C12orf4	NM_020374.4	c.1043_1044delCA	p.Thr348fs	frameshift_variant	9/14	ENST00000261250.8	NP_065107.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
C12orf4	ENST00000261250.8	c.1043_1044delCA	p.Thr348fs	frameshift_variant	9/14	1	NM_020374.4	ENSP00000261250.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000287 AC: 4 AN: 1394198 Hom.: 0 AF XY: 0.00000578 AC XY: 4 AN XY: 691614

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: 0.00000371

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Intellectual disability, autosomal recessive 66 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Dec 21, 2023

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with intellectual developmental disorder, autosomal recessive 66, (MIM#618221). (I) 0106 - This gene is associated with autosomal recessive disease. (I) 0201 - Variant is predicted to cause nonsense-mediated decay (NMD) and loss of protein (premature termination codon is located at least 54 nucleotides upstream of the final exon-exon junction). (SP) 0251 - This variant is heterozygous. (I) 0301 - Variant is absent from gnomAD (both v2 and v3). (SP) 0702 - Other NMD-predicted variants comparable to the one identified in this case have strong previous evidence for pathogenicity. These variants have been reported as likely pathogenic and pathogenic, and observed in homozygous individuals with intellectual disability (DECIPHER, PMID: 27311568, VCGS). (SP) 0807 - This variant has no previous evidence of pathogenicity. (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1207 - Parental origin of the variant is unresolved, as both parents are heterozygous (by trio analysis). (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.090		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr12-4626344;