chr9-6644613-C-A

Variant names:

• chr9-6644613-C-A
• rs978795483
• NM_000170.3:c.334+1G>T

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000170.3(GLDC):​c.334+1G>T variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.0000124 in 1,454,378 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.000012 (0 hom.)
• Consequence: GLDC NM_000170.3 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 6.64
• Publications: 0 publications found

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

LINC02851 (HGNC:):

ACMG classification

Our verdict: Pathogenic. The variant received 18 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 9-6644613-C-A is Pathogenic according to our data. Variant chr9-6644613-C-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 557987.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000170.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GLDC	NM_000170.3	MANE Select	c.334+1G>T		splice_donor intron	N/A	NP_000161.2	P23378

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GLDC	ENST00000321612.8	TSL:1 MANE Select	c.334+1G>T		splice_donor intron	N/A	ENSP00000370737.4	P23378
	GLDC	ENST00000920236.1		c.334+1G>T		splice_donor intron	N/A	ENSP00000590295.1
	GLDC	ENST00000953081.1		c.334+1G>T		splice_donor intron	N/A	ENSP00000623139.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 0.0000124 AC: 18 AN: 1454378 Hom.: 0 Cov.: 29 AF XY: 0.0000152 AC XY: 11 AN XY: 724136

African (AFR) AF: 0.00 AC: 0 AN: 33324

American (AMR) AF: 0.00 AC: 0 AN: 44718

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26094

East Asian (EAS) AF: 0.00 AC: 0 AN: 39658

South Asian (SAS) AF: 0.00 AC: 0 AN: 86116

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53328

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5750

European-Non Finnish (NFE) AF: 0.0000154 AC: 17 AN: 1105250

Other (OTH) AF: 0.0000166 AC: 1 AN: 60140

GnomAD4 genome Cov.: 31

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ClinVar

ClinVar submissions

Significance: Pathogenic/Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
2	-	-	Glycine encephalopathy (2)
2	-	-	Glycine encephalopathy 1 (2)
1	-	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.34
CADD	Pathogenic	33
DANN	Uncertain	0.99
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.88
FATHMM_MKL	Uncertain	0.93	D
PhyloP100		6.6
GERP RS		4.7
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.97		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.97		Position offset: 1

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

Other links and lift over

dbSNP: rs978795483; hg19: chr9-6644613;