NM_001492.6:c.462_470dupGGCGGCGGC

Variant names:

• chr19-18869244-CT-CTGCCGCCGC
• NM_001492.6:c.463_470dupGCGGCGGC

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_001492.6(GDF1):​c.463_470dupGCGGCGGC​(p.Ala158ArgfsTer11) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 32)
• Consequence: GDF1 NM_001492.6 frameshift
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.179
• Publications: 0 publications found

Genes affected

GDF1 (HGNC:4214): (growth differentiation factor 1) This gene encodes a secreted ligand of the TGF-beta (transforming growth factor-beta) superfamily of proteins. Ligands of this family bind various TGF-beta receptors leading to recruitment and activation of SMAD family transcription factors that regulate gene expression. The encoded preproprotein is proteolytically processed to generate each subunit of the disulfide-linked homodimer. Studies in rodents suggest that this protein is involved in the establishment of left-right asymmetry in early embryogenesis and in neural development in later embryogenesis. The encoded protein is translated from a bicistronic mRNA that also encodes ceramide synthase 1. Mutations in this gene are associated with several congenital cardiovascular malformations. [provided by RefSeq, Jul 2016]

CERS1 (HGNC:14253): (ceramide synthase 1) This gene encodes a ceramide synthase enzyme, which catalyzes the synthesis of ceramide, the hydrophobic moiety of sphingolipids. The encoded enzyme synthesizes 18-carbon (C18) ceramide in brain neurons. Elevated expression of this gene may be associated with increased longevity, while decreased expression of this gene may be associated with myoclonus epilepsy with dementia in human patients. This protein is transcribed from a monocistronic mRNA as well as a bicistronic mRNA, which also encodes growth differentiation factor 1. [provided by RefSeq, Jul 2016]

CERS1 Gene-Disease associations (from GenCC):

• progressive myoclonic epilepsy type 8

  Inheritance: AR Classification: STRONG, SUPPORTIVE, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Orphanet
• progressive myoclonus epilepsy

  Inheritance: AR Classification: MODERATE Submitted by: ClinGen

ACMG classification

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

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 22 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001492.6. 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
	GDF1	NM_001492.6	MANE Select	c.463_470dupGCGGCGGC	p.Ala158ArgfsTer11	frameshift	Exon 8 of 8	NP_001483.3
	CERS1	NM_021267.5	MANE Select	c.*732_*739dupGCGGCGGC		3_prime_UTR	Exon 8 of 8	NP_067090.1	P27544-1
	GDF1	NM_001387438.1		c.463_470dupGCGGCGGC	p.Ala158ArgfsTer11	frameshift	Exon 5 of 5	NP_001374367.1	P27539

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GDF1	ENST00000247005.8	TSL:1 MANE Select	c.463_470dupGCGGCGGC	p.Ala158ArgfsTer11	frameshift	Exon 8 of 8	ENSP00000247005.5	P27539
	CERS1	ENST00000623882.4	TSL:1 MANE Select	c.*732_*739dupGCGGCGGC		3_prime_UTR	Exon 8 of 8	ENSP00000485308.1	P27544-1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		0.18

Splicing

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr19-18980053;