chr19-18879307-G-T

Variant names:

• chr19-18879307-G-T
• rs781327266
• NM_021267.5:c.834C>A

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_021267.5(CERS1):​c.834C>A​(p.Ile278Ile) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,472 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign 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. I278I) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: CERS1 NM_021267.5 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 2.58
• Publications: 0 publications found

Genes affected

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]

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]

GDF1 Gene-Disease associations (from GenCC):

• right atrial isomerism

  Inheritance: AR Classification: STRONG, SUPPORTIVE, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, Ambry Genetics
• congenital heart defects, multiple types, 6

  Inheritance: AD Classification: LIMITED, NO_KNOWN Submitted by: Illumina, Ambry Genetics
• conotruncal heart malformations

  Inheritance: Unknown Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.5).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_021267.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CERS1	NM_021267.5	MANE Select	c.834C>A	p.Ile278Ile	synonymous	Exon 5 of 8	NP_067090.1
	GDF1	NM_001492.6	MANE Select	c.-489C>A		5_prime_UTR	Exon 5 of 8	NP_001483.3
	CERS1	NM_001387439.1		c.834C>A	p.Ile278Ile	synonymous	Exon 5 of 7	NP_001374368.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CERS1	ENST00000623882.4	TSL:1 MANE Select	c.834C>A	p.Ile278Ile	synonymous	Exon 5 of 8	ENSP00000485308.1
	CERS1	ENST00000429504.6	TSL:1	c.834C>A	p.Ile278Ile	synonymous	Exon 5 of 6	ENSP00000389044.1
	CERS1	ENST00000542296.6	TSL:1	c.540C>A	p.Ile180Ile	synonymous	Exon 5 of 6	ENSP00000437648.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000411 AC: 1 AN: 243116 AF XY: 0.00

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460472 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 726372

African (AFR) AF: 0.00 AC: 0 AN: 33472

American (AMR) AF: 0.00 AC: 0 AN: 44492

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26098

East Asian (EAS) AF: 0.00 AC: 0 AN: 39678

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 85870

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

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5762

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111438

Other (OTH) AF: 0.00 AC: 0 AN: 60334

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.50
CADD	Benign	5.1
DANN	Benign	0.90
PhyloP100		2.6

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

Other links and lift over

dbSNP: rs781327266; hg19: chr19-18990116;