9-6554674-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1 PM2 PP3

The NM_000170.3(GLDC):c.2310C>G(p.Ile770Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000687 in 1,455,194 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. I770I) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: GLDC NM_000170.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.491

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 5 ACMG points.

• PM1: In a hotspot region, there are 8 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 5 uncertain in NM_000170.3
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.791

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GLDC	NM_000170.3	c.2310C>G	p.Ile770Met	missense_variant	19/25	ENST00000321612.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GLDC	ENST00000321612.8	c.2310C>G	p.Ile770Met	missense_variant	19/25	1	NM_000170.3	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000401 AC: 1 AN: 249682 Hom.: 0 AF XY: 0.00000741 AC XY: 1 AN XY: 134892

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000545

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.87e-7 AC: 1 AN: 1455194 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 724082

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.: 33

ExAC AF: 0.00000824 AC: 1

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.30
BayesDel_addAF	Pathogenic	0.20	D
BayesDel_noAF	Pathogenic	0.22
Cadd	Benign	13
Dann	Uncertain	0.99
DEOGEN2	Uncertain	0.71	D;.;.;.
Eigen	Benign	-0.18
Eigen_PC	Benign	-0.49
FATHMM_MKL	Benign	0.24	N
LIST_S2	Pathogenic	0.99	D;T;D;D
M_CAP	Pathogenic	0.80	D
MetaRNN	Pathogenic	0.79	D;D;D;D
MetaSVM	Pathogenic	0.83	D
MutationAssessor	Pathogenic	4.3	H;.;.;.
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.57	T
PROVEAN	Uncertain	-2.8	D;.;.;.
REVEL	Pathogenic	0.70
Sift	Pathogenic	0.0	D;.;.;.
Sift4G	Pathogenic	0.0	D;.;.;.
Polyphen		1.0	D;.;.;.
Vest4		0.84
MutPred		0.65		Gain of disorder (P = 0.0234);.;.;.;
MVP		0.97
MPC		0.28
ClinPred		1.0	D
GERP RS		-7.8
Varity_R		0.90
gMVP		0.92

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.23		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.23		Position offset: -5

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

Publications

LitVar

Other links and lift over

dbSNP: rs765661419; hg19: chr9-6554674;