2-3387715-TC-T

Position:

• chr2-3387715-TC-T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PVS1_Strong PM2 PP5_Moderate

The NM_016030.6(TRAPPC12):​c.94delC​(p.Gln32fs) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: TRAPPC12 NM_016030.6 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: -0.220

Genes affected

TRAPPC12 (HGNC:24284): (trafficking protein particle complex subunit 12) Involved in several processes, including endoplasmic reticulum to Golgi vesicle-mediated transport; positive regulation of protein localization to kinetochore; and regulation of kinetochore assembly. Located in Golgi apparatus; kinetochore; and nucleoplasm. Part of TRAPP complex. Colocalizes with endoplasmic reticulum-Golgi intermediate compartment and perinuclear region of cytoplasm. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.957 CDS is truncated, and there are 0 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 2-3387715-TC-T is Pathogenic according to our data. Variant chr2-3387715-TC-T is described in ClinVar as [Pathogenic]. Clinvar id is 3254924.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TRAPPC12	NM_016030.6	c.94delC	p.Gln32fs	frameshift_variant	2/12	ENST00000324266.10	NP_057114.5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TRAPPC12	ENST00000324266.10	c.94delC	p.Gln32fs	frameshift_variant	2/12	1	NM_016030.6	ENSP00000324318.5
TRAPPC12	ENST00000382110.6	c.94delC	p.Gln32fs	frameshift_variant	2/12	2		ENSP00000371544.2
TRAPPC12	ENST00000482645.1	n.255delC		non_coding_transcript_exon_variant	2/2	2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Early-onset progressive encephalopathy-hearing loss-pons hypoplasia-brain atrophy syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Jul 17, 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 encephalopathy, progressive, early-onset, with brain atrophy and spasticity (MIM#617669). (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 individuals or fetuses with a neurological phenotype (DECIPHER, PMID: 36658419, PMID: 32347653). (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) 1102 - Strong phenotype match for this individual. (SP) 1201 - Heterozygous variant detected in trans with a second pathogenic heterozygous variant (p.(Lys608*)) in a recessive disease. (I) 1205 - This variant has been shown to be maternally inherited (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)		0.0		Details are displayed if max score is > 0.2

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr2-3391486;