9-6554703-C-T

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PS1PM1PM2PP3_ModeratePP5_Very_Strong

The NM_000170.3(GLDC):​c.2281G>A​(p.Gly761Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000583 in 1,612,486 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 13/23 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another nucleotide change resulting in same amino acid change has been previously reported as Pathogenicin Lovd.

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000060 ( 0 hom. )

Consequence

GLDC
NM_000170.3 missense

Scores

17
1
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4

Conservation

PhyloP100: 7.54
Variant links:
Genes affected
GLDC (HGNC:4313): (glycine decarboxylase) Degradation of glycine is brought about by the glycine cleavage system, which is composed of four mitochondrial protein components: P protein (a pyridoxal phosphate-dependent glycine decarboxylase), H protein (a lipoic acid-containing protein), T protein (a tetrahydrofolate-requiring enzyme), and L protein (a lipoamide dehydrogenase). The protein encoded by this gene is the P protein, which binds to glycine and enables the methylamine group from glycine to be transferred to the T protein. Defects in this gene are a cause of nonketotic hyperglycinemia (NKH).[provided by RefSeq, Jan 2010]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PS1
Transcript NM_000170.3 (GLDC) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in Lovd
PM1
In a turn (size 2) in uniprot entity GCSP_HUMAN there are 7 pathogenic changes around while only 0 benign (100%) in NM_000170.3
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.925
PP5
Variant 9-6554703-C-T is Pathogenic according to our data. Variant chr9-6554703-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 555815.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr9-6554703-C-T is described in Lovd as [Pathogenic]. Variant chr9-6554703-C-T is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
GLDCNM_000170.3 linkuse as main transcriptc.2281G>A p.Gly761Arg missense_variant 19/25 ENST00000321612.8 NP_000161.2 P23378

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
GLDCENST00000321612.8 linkuse as main transcriptc.2281G>A p.Gly761Arg missense_variant 19/251 NM_000170.3 ENSP00000370737.4 P23378

Frequencies

GnomAD3 genomes
AF:
0.0000394
AC:
6
AN:
152248
Hom.:
0
Cov.:
33
show subpopulations
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:
0.000565
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.000168
AC:
42
AN:
250606
Hom.:
0
AF XY:
0.000148
AC XY:
20
AN XY:
135392
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00181
Gnomad NFE exome
AF:
0.00000882
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000603
AC:
88
AN:
1460238
Hom.:
0
Cov.:
31
AF XY:
0.0000523
AC XY:
38
AN XY:
726390
show subpopulations
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:
0.00144
Gnomad4 NFE exome
AF:
0.00000630
Gnomad4 OTH exome
AF:
0.0000498
GnomAD4 genome
AF:
0.0000394
AC:
6
AN:
152248
Hom.:
0
Cov.:
33
AF XY:
0.0000672
AC XY:
5
AN XY:
74386
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.000565
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.555
Hom.:
8748
Bravo
AF:
0.0000113
ExAC
AF:
0.0000906
AC:
11

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Glycine encephalopathy Pathogenic:3
Pathogenic, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpJun 19, 2020Variant summary: GLDC c.2281G>A (p.Gly761Arg) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 0.00017 in 250606 control chromosomes (gnomAD). This frequency is not higher than expected for a pathogenic variant in GLDC causing Glycine Encephalopathy (Non-Ketotic Hyperglycinemia) (0.00017 vs 0.0031), allowing no conclusion about variant significance. c.2281G>A has been reported in the literature in multiple individuals affected with Glycine Encephalopathy (Non-Ketotic Hyperglycinemia) (e.g. Applegarth_2001, Coughlin_2017). These data indicate that the variant is very likely to be associated with disease. Experimental evidence evaluating an impact on protein function demonstrated the variant had no measurable residual activity (Swanson_2015). Two ClinVar submitters (evaluation after 2014) cite the variant as pathogenic/likely pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 05, 2024This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 761 of the GLDC protein (p.Gly761Arg). This variant is present in population databases (rs386833549, gnomAD 0.2%). This missense change has been observed in individual(s) with glycine encephalopathy (PMID: 27362913). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 555815). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt GLDC protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects GLDC function (PMID: 26179960). 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. -
Likely pathogenic, criteria provided, single submitterclinical testingCounsylDec 22, 2017- -
not provided Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingGeneDxAug 24, 2021In-silico splice models predict that c.2281 G>A may create a cryptic splice acceptor site in exon 19 that could supplant the natural splice acceptor site. However, in the absence of RNA/functional studies, the actual effect of the c.2281 G>A change in this individual is unknown. If c.2281 G>A does not alter splicing, it will result in the G761R missense change.; This variant is associated with the following publications: (PMID: 16601880, 11592811, 26179960, 33726816, 27362913) -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
1.0
BayesDel_addAF
Pathogenic
0.46
D
BayesDel_noAF
Pathogenic
0.59
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.86
D;.;.
Eigen
Pathogenic
1.1
Eigen_PC
Pathogenic
0.95
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.90
D;D;D
M_CAP
Pathogenic
0.73
D
MetaRNN
Pathogenic
0.92
D;D;D
MetaSVM
Pathogenic
0.96
D
MutationAssessor
Pathogenic
4.5
H;.;.
PrimateAI
Pathogenic
0.84
D
PROVEAN
Pathogenic
-7.6
D;.;.
REVEL
Pathogenic
0.96
Sift
Pathogenic
0.0
D;.;.
Sift4G
Pathogenic
0.0
D;.;.
Polyphen
1.0
D;.;.
Vest4
0.99
MutPred
0.91
Loss of relative solvent accessibility (P = 0.0071);.;.;
MVP
1.0
MPC
0.34
ClinPred
0.97
D
GERP RS
5.4
Varity_R
0.96
gMVP
0.99

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.24
Details are displayed if max score is > 0.2
DS_DL_spliceai
0.24
Position offset: -34

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs386833549; hg19: chr9-6554703; COSMIC: COSV105221139; COSMIC: COSV105221139; API