1-53196977-C-CG

Variant names:

• chr1-53196977-C-CG
• NM_000098.3:c.38dupG

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_000098.3(CPT2):​c.38dupG​(p.Ala15ArgfsTer44) 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 (★). Synonymous variant affecting the same amino acid position (i.e. G13G) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: CPT2 NM_000098.3 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 0.472
• Publications: 0 publications found

Genes affected

CPT2 (HGNC:2330): (carnitine palmitoyltransferase 2) The protein encoded by this gene is a nuclear protein which is transported to the mitochondrial inner membrane. Together with carnitine palmitoyltransferase I, the encoded protein oxidizes long-chain fatty acids in the mitochondria. Defects in this gene are associated with mitochondrial long-chain fatty-acid (LCFA) oxidation disorders. [provided by RefSeq, Jul 2008]

CPT2 Gene-Disease associations (from GenCC):

• carnitine palmitoyltransferase II deficiency

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen, Myriad Women’s Health
• carnitine palmitoyl transferase II deficiency, myopathic form

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, PanelApp Australia
• carnitine palmitoyl transferase II deficiency, neonatal form

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), PanelApp Australia
• carnitine palmitoyl transferase II deficiency, severe infantile form

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: PanelApp Australia, Orphanet
• encephalopathy, acute, infection-induced, susceptibility to, 4

  Inheritance: Unknown Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Pathogenic. The variant received 12 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. There are 216 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 1-53196977-C-CG is Pathogenic according to our data. Variant chr1-53196977-C-CG is described in ClinVar as [Pathogenic]. Clinvar id is 3725052.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CPT2	NM_000098.3	c.38dupG	p.Ala15ArgfsTer44	frameshift_variant	Exon 1 of 5	ENST00000371486.4	NP_000089.1
CPT2	NM_001330589.2	c.38dupG	p.Ala15ArgfsTer44	frameshift_variant	Exon 1 of 5		NP_001317518.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CPT2	ENST00000371486.4	c.38dupG	p.Ala15ArgfsTer44	frameshift_variant	Exon 1 of 5	1	NM_000098.3	ENSP00000360541.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Carnitine palmitoyltransferase II deficiency Pathogenic:1

Nov 23, 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.Ala15Argfs*44) in the CPT2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in CPT2 are known to be pathogenic (PMID: 16781677, 16996287). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with CPT2-related conditions. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		0.47

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

Other links and lift over

hg19: chr1-53662649;