chr19-18868688-G-C

Position:

• chr19-18868688-G-C

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_001492.6(GDF1):​c.1028C>G​(p.Ser343Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. S343S) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: GDF1 NM_001492.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.67

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM1: In a chain Embryonic growth/differentiation factor 1 (size 118) in uniprot entity GDF1_HUMAN there are 7 pathogenic changes around while only 2 benign (78%) in NM_001492.6
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.861

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GDF1	NM_001492.6	c.1028C>G	p.Ser343Trp	missense_variant	8/8	ENST00000247005.8
CERS1	NM_021267.5	c.*1297C>G		3_prime_UTR_variant	8/8	ENST00000623882.4
GDF1	NM_001387438.1	c.1028C>G	p.Ser343Trp	missense_variant	5/5
CERS1	NM_001387440.1	c.*1889C>G		3_prime_UTR_variant	7/7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GDF1	ENST00000247005.8	c.1028C>G	p.Ser343Trp	missense_variant	8/8	1	NM_001492.6	P1
CERS1	ENST00000623882.4	c.*1297C>G		3_prime_UTR_variant	8/8	1	NM_021267.5	P2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1412402 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 698278

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 08, 2019

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 disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with GDF1-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces serine with tryptophan at codon 343 of the GDF1 protein (p.Ser343Trp). The serine residue is highly conserved and there is a large physicochemical difference between serine and tryptophan. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.78
BayesDel_addAF	Pathogenic	0.20	D
BayesDel_noAF	Uncertain	0.050
CADD	Pathogenic	32
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.96	D;.
Eigen	Uncertain	0.38
Eigen_PC	Uncertain	0.30
FATHMM_MKL	Benign	0.71	D
LIST_S2	Pathogenic	0.98	D;.
M_CAP	Pathogenic	0.72	D
MetaRNN	Pathogenic	0.86	D;D
MetaSVM	Pathogenic	0.90	D
MutationAssessor	Pathogenic	3.4	M;.
MutationTaster	Benign	1.0	D;D
PROVEAN	Pathogenic	-6.1	D;.
REVEL	Pathogenic	0.76
Sift	Pathogenic	0.0	D;.
Sift4G	Pathogenic	0.0	D;D
Vest4		0.77
MutPred		0.61		Loss of phosphorylation at S343 (P = 0.0662);Loss of phosphorylation at S343 (P = 0.0662);
MVP		0.50
MPC		2.4
ClinPred		1.0	D
GERP RS		3.8
Varity_R		0.83
gMVP		0.92

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: rs2055898931; hg19: chr19-18979497;