rs199497486

Variant names:

• chr5-126592663-C-A
• rs199497486
• NM_001182.5:c.312+1G>T

Your query was ambiguous. Multiple possible variants found:

• chr5-126592663-C-A
• chr5-126592663-C-T

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1_Moderate PM2 PP5_Very_Strong

The NM_001182.5(ALDH7A1):​c.312+1G>T variant causes a splice donor, intron change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: ALDH7A1 NM_001182.5 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 7.20
• Publications: 0 publications found

Genes affected

ALDH7A1 (HGNC:877): (aldehyde dehydrogenase 7 family member A1) The protein encoded by this gene is a member of subfamily 7 in the aldehyde dehydrogenase gene family. These enzymes are thought to play a major role in the detoxification of aldehydes generated by alcohol metabolism and lipid peroxidation. This particular member has homology to a previously described protein from the green garden pea, the 26g pea turgor protein. It is also involved in lysine catabolism that is known to occur in the mitochondrial matrix. Recent reports show that this protein is found both in the cytosol and the mitochondria, and the two forms likely arise from the use of alternative translation initiation sites. An additional variant encoding a different isoform has also been found for this gene. Mutations in this gene are associated with pyridoxine-dependent epilepsy. Several related pseudogenes have also been identified. [provided by RefSeq, Jan 2011]

ALDH7A1 Gene-Disease associations (from GenCC):

• pyridoxine-dependent epilepsy

  Inheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: Illumina, Orphanet, ClinGen
• pyridoxine-dependent epilepsy caused by ALDH7A1 mutant

  Inheritance: AR, AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.04074074 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 5-126592663-C-A is Pathogenic according to our data. Variant chr5-126592663-C-A is described in ClinVar as Pathogenic. ClinVar VariationId is 2010345.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
ALDH7A1	NM_001182.5	c.312+1G>T		splice_donor_variant, intron_variant	Intron 3 of 17	ENST00000409134.8	NP_001173.2
ALDH7A1	NM_001201377.2	c.228+1G>T		splice_donor_variant, intron_variant	Intron 3 of 17		NP_001188306.1
ALDH7A1	NM_001202404.2	c.312+1G>T		splice_donor_variant, intron_variant	Intron 3 of 15		NP_001189333.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ALDH7A1	ENST00000409134.8	c.312+1G>T		splice_donor_variant, intron_variant	Intron 3 of 17	1	NM_001182.5	ENSP00000387123.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Pyridoxine-dependent epilepsy Pathogenic:2

Nov 19, 2023

Revvity Omics, Revvity

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jun 24, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects a donor splice site in intron 3 of the ALDH7A1 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in ALDH7A1 are known to be pathogenic (PMID: 16491085, 20554659). This variant is not present in population databases (gnomAD no frequency). Disruption of this splice site has been observed in individual(s) with pyridoxine-dependent epilepsy (PMID: 21733724). It has also been observed to segregate with disease in related individuals. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.42
CADD	Pathogenic	33
DANN	Uncertain	1.0
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.95
FATHMM_MKL	Pathogenic	0.99	D
PhyloP100		7.2
GERP RS		4.7
Mutation Taster		=0/100	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_DL_spliceai		1.0		Position offset: 1

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

Other links and lift over

dbSNP: rs199497486; hg19: chr5-125928355;