14-50247224-AGG-A

Variant names:

• chr14-50247224-AGG-A
• NM_024884.3:c.1224_1225delCC

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_Strong PM2

The NM_024884.3(L2HGDH):​c.1224_1225delCC​(p.Leu409GlyfsTer2) 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 Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: L2HGDH NM_024884.3 frameshift
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.09

Genes affected

L2HGDH (HGNC:20499): (L-2-hydroxyglutarate dehydrogenase) This gene encodes L-2-hydroxyglutarate dehydrogenase, a FAD-dependent enzyme that oxidizes L-2-hydroxyglutarate to alpha-ketoglutarate in a variety of mammalian tissues. Mutations in this gene cause L-2-hydroxyglutaric aciduria, a rare autosomal recessive neurometabolic disorder resulting in moderate to severe cognitive disability. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 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 5 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
L2HGDH	NM_024884.3	c.1224_1225delCC	p.Leu409GlyfsTer2	frameshift_variant	Exon 10 of 10	ENST00000267436.9	NP_079160.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
L2HGDH	ENST00000267436.9	c.1224_1225delCC	p.Leu409GlyfsTer2	frameshift_variant	Exon 10 of 10	1	NM_024884.3	ENSP00000267436.4
L2HGDH	ENST00000261699.8	c.1197-9501_1197-9500delCC		intron_variant	Intron 9 of 9	1		ENSP00000261699.4
L2HGDH	ENST00000421284.7	c.1224_1225delCC	p.Leu409GlyfsTer2	frameshift_variant	Exon 10 of 11	2		ENSP00000405559.3

Frequencies

GnomAD3 genomes Cov.: 33

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

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

L-2-hydroxyglutaric aciduria Uncertain:1

Aug 21, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Leu409Glyfs*2) in the L2HGDH gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 55 amino acid(s) of the L2HGDH protein. This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with L2HGDH-related conditions. Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. This variant disrupts a region of the L2HGDH protein in which other variant(s) (p.His434Pro) have been observed in individuals with L2HGDH-related conditions (PMID: 16134148). This suggests that this is a clinically significant region of the protein, and that variants that disrupt it are likely to be disease-causing. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

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: chr14-50713942;