NM_000098.3:c.748_749delAA

Variant names:

• chr1-53210420-GAA-G
• rs1187631754
• NM_000098.3:c.748_749delAA

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000098.3(CPT2):​c.748_749delAA​(p.Asn250PhefsTer5) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,186 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: CPT2 NM_000098.3 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 2.37
• Publications: 1 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)

ENSG00000236723 (HGNC:):

ACMG classification

Our verdict: Pathogenic. The variant received 18 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 1-53210420-GAA-G is Pathogenic according to our data. Variant chr1-53210420-GAA-G is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 554639.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
CPT2	NM_000098.3	c.748_749delAA	p.Asn250PhefsTer5	frameshift_variant	Exon 4 of 5	ENST00000371486.4	NP_000089.1
CPT2	NM_001330589.2	c.748_749delAA	p.Asn250PhefsTer5	frameshift_variant	Exon 4 of 5		NP_001317518.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CPT2	ENST00000371486.4	c.748_749delAA	p.Asn250PhefsTer5	frameshift_variant	Exon 4 of 5	1	NM_000098.3	ENSP00000360541.3

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152186 Hom.: 0 Cov.: 32

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: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152186 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74348

African (AFR) AF: 0.00 AC: 0 AN: 41428

American (AMR) AF: 0.00 AC: 0 AN: 15284

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5196

South Asian (SAS) AF: 0.00 AC: 0 AN: 4828

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10618

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68042

Other (OTH) AF: 0.00 AC: 0 AN: 2094

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Carnitine palmitoyl transferase II deficiency, severe infantile form Pathogenic:2

Apr 11, 2023

Genome-Nilou Lab

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Oct 27, 2017

Counsyl

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Encephalopathy, acute, infection-induced, susceptibility to, 4 Pathogenic:1

Jan 19, 2024

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Carnitine palmitoyltransferase II deficiency Pathogenic:1

Jun 29, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

For these reasons, this variant has been classified as Pathogenic. This sequence change creates a premature translational stop signal (p.Asn250Phefs*5) 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 premature translational stop signal has been observed in individual(s) with CPT2 deficiency (PMID: 18925671). ClinVar contains an entry for this variant (Variation ID: 554639). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		2.4
Mutation Taster		=4/196	disease causing (ClinVar)

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

dbSNP: rs1187631754; hg19: chr1-53676092;