19-12893531-G-T

Variant names:

• chr19-12893531-G-T
• rs755586631
• NM_000159.4:c.383G>T

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PM1 PM2 PM5 PP3_Strong

The NM_000159.4(GCDH):​c.383G>T​(p.Arg128Leu) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,602 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R128Q) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: GCDH NM_000159.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.33
• Publications: 0 publications found

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]

GCDH Gene-Disease associations (from GenCC):

• glutaryl-CoA dehydrogenase deficiency

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: ClinGen, Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Orphanet, G2P, Myriad Women’s Health

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PM1: In a hotspot region, there are 10 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in NM_000159.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr19-12893531-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 189063.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.96

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GCDH	NM_000159.4	c.383G>T	p.Arg128Leu	missense_variant	Exon 6 of 12	ENST00000222214.10	NP_000150.1
GCDH	NM_013976.5	c.383G>T	p.Arg128Leu	missense_variant	Exon 6 of 12		NP_039663.1
GCDH	NR_102316.1	n.546G>T		non_coding_transcript_exon_variant	Exon 6 of 12
GCDH	NR_102317.1	n.799G>T		non_coding_transcript_exon_variant	Exon 5 of 11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GCDH	ENST00000222214.10	c.383G>T	p.Arg128Leu	missense_variant	Exon 6 of 12	1	NM_000159.4	ENSP00000222214.4

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461602 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727118

African (AFR) AF: 0.00 AC: 0 AN: 33474

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39694

South Asian (SAS) AF: 0.0000232 AC: 2 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53412

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111758

Other (OTH) AF: 0.00 AC: 0 AN: 60386

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Glutaric aciduria, type 1 Uncertain:1

-

Neuberg Centre For Genomic Medicine, NCGM

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The missense variant p.R128L in GCDH (NM_000159.4) has not been reported previously as a pathogenic variant nor as a benign variant, to our knowledge. Another missense mutation affecting the same amino acid R128Q has been reported as Pathogenic (Boy N et al, 2017). The p.R128L variant is novel (not in any individuals) in gnomAD Exomes and is novel (not in any individuals) in 1000 Genomes. There is a moderate physicochemical difference between arginine and leucine. The p.R128L missense variant is predicted to be damaging by both SIFT and PolyPhen2. The nucleotide c.383 in GCDH is predicted conserved by GERP++ and PhyloP across 100 vertebrates. For these reasons, this variant has been classified as Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.57
BayesDel_addAF	Pathogenic	0.51	D
BayesDel_noAF	Pathogenic	0.50
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.98	D;.;D;D
Eigen	Pathogenic	0.76
Eigen_PC	Pathogenic	0.68
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	.;D;D;D
M_CAP	Pathogenic	0.84	D
MetaRNN	Pathogenic	0.96	D;D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Uncertain	2.6	M;.;M;.
PhyloP100		6.3
PrimateAI	Uncertain	0.60	T
PROVEAN	Pathogenic	-6.3	D;.;.;.
REVEL	Pathogenic	0.95
Sift	Pathogenic	0.0	D;.;.;.
Sift4G	Benign	0.18	T;D;T;D
Polyphen		1.0	D;.;D;.
Vest4		0.90
MutPred		0.78		Loss of MoRF binding (P = 0.0638);.;Loss of MoRF binding (P = 0.0638);.;
MVP		0.99
MPC		1.1
ClinPred		1.0	D
GERP RS		4.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.93
gMVP		0.92
Mutation Taster		=3/97	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		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: rs755586631; hg19: chr19-13004345;