rs1214310966

chr9-6534786-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1 PM2

The NM_000170.3(GLDC):c.2841G>A(p.Met947Ile) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000056 in 1,427,800 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000056 (0 hom.)
• Consequence: GLDC NM_000170.3 missense, splice_region
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 7.21

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 4 uncertain in NM_000170.3
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GLDC	NM_000170.3	c.2841G>A	p.Met947Ile	missense_variant, splice_region_variant	24/25	ENST00000321612.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GLDC	ENST00000321612.8	c.2841G>A	p.Met947Ile	missense_variant, splice_region_variant	24/25	1	NM_000170.3	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000399 AC: 1 AN: 250940 Hom.: 0 AF XY: 0.00000737 AC XY: 1 AN XY: 135600

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 SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000881

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000560 AC: 8 AN: 1427800 Hom.: 0 Cov.: 25 AF XY: 0.00000702 AC XY: 5 AN XY: 712666

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000740

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Non-ketotic hyperglycinemia Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Feb 24, 2022	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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. ClinVar contains an entry for this variant (Variation ID: 556776). This missense change has been observed in individual(s) with nonketotic hyperglycinemia (PMID: 27362913). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. This variant is present in population databases (no rsID available, gnomAD 0.0009%). This sequence change replaces methionine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 947 of the GLDC protein (p.Met947Ile). -
Uncertain significance, criteria provided, single submitter	clinical testing	Counsyl	Feb 22, 2018	- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.68
BayesDel_addAF	Pathogenic	0.22	D
BayesDel_noAF	Uncertain	0.070
Cadd	Uncertain	25
Dann	Uncertain	0.99
DEOGEN2	Uncertain	0.55	D;.;.;.
Eigen	Uncertain	0.56
Eigen_PC	Uncertain	0.60
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.99	D;D;D;D
M_CAP	Uncertain	0.13	D
MetaRNN	Uncertain	0.66	D;D;D;D
MetaSVM	Uncertain	0.31	D
MutationAssessor	Uncertain	2.4	M;.;.;.
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.69	T
PROVEAN	Benign	-2.2	N;.;.;.
REVEL	Uncertain	0.64
Sift	Benign	0.095	T;.;.;.
Sift4G	Uncertain	0.040	D;.;.;.
Polyphen		0.81	P;.;.;.
Vest4		0.84
MutPred		0.36		Gain of catalytic residue at P949 (P = 0.0307);.;.;.;
MVP		0.94
MPC		0.053
ClinPred		0.89	D
GERP RS		5.4
Varity_R		0.54
gMVP		0.83

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

LitVar

Other links and lift over

dbSNP: rs1214310966; hg19: chr9-6534786;