NM_000170.3:c.2305C>A

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PM1PM2PM5PP3_Strong

The NM_000170.3(GLDC):​c.2305C>A​(p.Pro769Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000186 in 1,609,172 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. P769S) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000018 ( 0 hom. )

Consequence

GLDC
NM_000170.3 missense

Scores

14
4
1

Clinical Significance

Uncertain significance criteria provided, single submitter U:3

Conservation

PhyloP100: 9.57

Publications

0 publications found
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]
GLDC Gene-Disease associations (from GenCC):
  • glycine encephalopathy
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Myriad Women’s Health, Labcorp Genetics (formerly Invitae), ClinGen
  • glycine encephalopathy 1
    Inheritance: AR Classification: DEFINITIVE Submitted by: G2P
  • infantile glycine encephalopathy
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • neonatal glycine encephalopathy
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • atypical glycine encephalopathy
    Inheritance: Unknown Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

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

PM1
In a hotspot region, there are 13 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 4 uncertain in NM_000170.3
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr9-6554678-G-A is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 56071.Status of the report is no_assertion_criteria_provided, 0 stars.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.963

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GLDCNM_000170.3 linkc.2305C>A p.Pro769Thr missense_variant Exon 19 of 25 ENST00000321612.8 NP_000161.2 P23378

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GLDCENST00000321612.8 linkc.2305C>A p.Pro769Thr missense_variant Exon 19 of 25 1 NM_000170.3 ENSP00000370737.4 P23378

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152204
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000400
AC:
1
AN:
250068
AF XY:
0.00000740
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000884
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000178
AC:
26
AN:
1456968
Hom.:
0
Cov.:
31
AF XY:
0.0000138
AC XY:
10
AN XY:
724944
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33374
American (AMR)
AF:
0.00
AC:
0
AN:
44642
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26100
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39674
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85888
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53402
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
4366
European-Non Finnish (NFE)
AF:
0.0000234
AC:
26
AN:
1109382
Other (OTH)
AF:
0.00
AC:
0
AN:
60140
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.465
Heterozygous variant carriers
0
1
3
4
6
7
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152204
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74366
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41444
American (AMR)
AF:
0.00
AC:
0
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5204
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68040
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.463
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000189
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Glycine encephalopathy Uncertain:2
Jun 10, 2021
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Oct 08, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces proline with threonine at codon 769 of the GLDC protein (p.Pro769Thr). The proline residue is highly conserved and there is a small physicochemical difference between proline and threonine. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the ExAC database. This missense change has been observed in individual(s) with glycine encephalopathy (PMID: 27362913; Invitae). In at least one individual the data is consistent with the variant being in trans (on the opposite chromosome) from a pathogenic variant. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). 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. -

Glycine encephalopathy 1 Uncertain:1
Oct 13, 2017
Counsyl
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.84
BayesDel_addAF
Pathogenic
0.57
D
BayesDel_noAF
Pathogenic
0.57
CADD
Pathogenic
31
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.83
D;.;.;.
Eigen
Pathogenic
1.1
Eigen_PC
Pathogenic
0.97
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
1.0
D;T;D;D
M_CAP
Pathogenic
0.72
D
MetaRNN
Pathogenic
0.96
D;D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
4.5
H;.;.;.
PhyloP100
9.6
PrimateAI
Uncertain
0.78
T
PROVEAN
Pathogenic
-7.6
D;.;.;.
REVEL
Pathogenic
0.95
Sift
Uncertain
0.0060
D;.;.;.
Sift4G
Uncertain
0.0070
D;.;.;.
Polyphen
1.0
D;.;.;.
Vest4
0.93
MutPred
0.80
Loss of disorder (P = 0.0793);.;.;.;
MVP
0.99
MPC
0.33
ClinPred
1.0
D
GERP RS
5.4
PromoterAI
0.017
Neutral
Varity_R
0.87
gMVP
0.96
Mutation Taster
=34/66
disease causing

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

Other links and lift over

dbSNP: rs751114163; hg19: chr9-6554679; API