NM_000159.4:c.271+1G>A

Variant names:

• chr19-12891975-G-A
• rs786204639
• NM_000159.4:c.271+1G>A

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PVS1_Strong PM2 PP5_Very_Strong

The NM_000159.4(GCDH):​c.271+1G>A variant causes a splice donor, intron change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,892 control chromosomes in the GnomAD database, with no homozygous occurrence. 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 Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: GCDH NM_000159.4 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 9.39

Genes affected

GCDH (HGNC:4189): (glutaryl-CoA dehydrogenase) The protein encoded by this gene belongs to the acyl-CoA dehydrogenase family. It catalyzes the oxidative decarboxylation of glutaryl-CoA to crotonyl-CoA and CO(2) in the degradative pathway of L-lysine, L-hydroxylysine, and L-tryptophan metabolism. It uses electron transfer flavoprotein as its electron acceptor. The enzyme exists in the mitochondrial matrix as a homotetramer of 45-kD subunits. Mutations in this gene result in the metabolic disorder glutaric aciduria type 1, which is also known as glutaric acidemia type I. Alternative splicing of this gene results in multiple transcript variants. A related pseudogene has been identified on chromosome 12. [provided by RefSeq, Mar 2013]

ACMG classification

Verdict is Pathogenic. Variant got 14 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.10933941 fraction of the gene. Cryptic splice site detected, with MaxEntScore 6.3, offset of 12, new splice context is: ctgGTgggt. Cryptic site results in inframe change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 19-12891975-G-A is Pathogenic according to our data. Variant chr19-12891975-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 189030.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr19-12891975-G-A is described in Lovd as [Pathogenic]. Variant chr19-12891975-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GCDH	NM_000159.4	c.271+1G>A		splice_donor_variant, intron_variant	Intron 4 of 11	ENST00000222214.10	NP_000150.1
GCDH	NM_013976.5	c.271+1G>A		splice_donor_variant, intron_variant	Intron 4 of 11		NP_039663.1
GCDH	NR_102316.1	n.379+1G>A		splice_donor_variant, intron_variant	Intron 4 of 11
GCDH	NR_102317.1	n.687+1G>A		splice_donor_variant, intron_variant	Intron 3 of 10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GCDH	ENST00000222214.10	c.271+1G>A		splice_donor_variant, intron_variant	Intron 4 of 11	1	NM_000159.4	ENSP00000222214.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461892 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 727246

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Glutaric aciduria, type 1 Pathogenic:2

Oct 21, 2014

Counsyl

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: literature only

- -

Feb 07, 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. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. This sequence change affects a donor splice site in intron 4 of the GCDH 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 GCDH are known to be pathogenic (PMID: 10699052, 11854167, 16602100). This variant is not present in population databases (gnomAD no frequency). Disruption of this splice site has been observed in individual(s) with glutaric acidemia type I (PMID: 11058907). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. This variant is also known as IVS3+1G>A. ClinVar contains an entry for this variant (Variation ID: 189030). -

not provided Pathogenic:1

Aug 17, 2018

Eurofins Ntd Llc (ga)

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.21
CADD	Pathogenic	35
DANN	Uncertain	0.99
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.81
FATHMM_MKL	Uncertain	0.95	D
GERP RS		3.6

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.55		Position offset: 11
DS_DL_spliceai		1.0		Position offset: -1

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

Publications

LitVar

Other links and lift over

dbSNP: rs786204639; hg19: chr19-13002789;