chr6-158119166-GCTGA-G

Position:

• chr6-158119166-GCTGA-G

Variant summary

Our verdict is Pathogenic. Variant got 20 ACMG points: 20P and 0B. PVS1 PM2 PP3_Moderate PP5_Very_Strong

The NM_032861.4(SERAC1):​c.1167_1170del​(p.Gln390ProfsTer29) variant causes a frameshift, splice region change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000087 in 1,608,906 control chromosomes in the GnomAD database, with no homozygous occurrence. 1/1 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000089 (0 hom.)
• Consequence: SERAC1 NM_032861.4 frameshift, splice_region
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 7.49

Genes affected

SERAC1 (HGNC:21061): (serine active site containing 1) The protein encoded by this gene is a phosphatidylglycerol remodeling protein found at the interface of mitochondria and endoplasmic reticula, where it mediates phospholipid exchange. The encoded protein plays a major role in mitochondrial function and intracellular cholesterol trafficking. Defects in this gene are a cause of 3-methylglutaconic aciduria with deafness, encephalopathy, and Leigh-like syndrome (MEGDEL). Two transcript variants, one protein-coding and the other non-protein coding, have been found for this gene. [provided by RefSeq, Aug 2012]

ACMG classification

Verdict is Pathogenic. Variant got 20 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 6-158119166-GCTGA-G is Pathogenic according to our data. Variant chr6-158119166-GCTGA-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 35558.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr6-158119166-GCTGA-G is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SERAC1	NM_032861.4	c.1167_1170del	p.Gln390ProfsTer29	frameshift_variant, splice_region_variant	12/17	ENST00000647468.2	NP_116250.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SERAC1	ENST00000647468.2	c.1167_1170del	p.Gln390ProfsTer29	frameshift_variant, splice_region_variant	12/17		NM_032861.4	ENSP00000496731	P1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152186 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.00000415 AC: 1 AN: 240762 Hom.: 0 AF XY: 0.00000769 AC XY: 1 AN XY: 130064

Gnomad AFR exome AF: 0.0000647

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

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: 0.00000892 AC: 13 AN: 1456720 Hom.: 0 AF XY: 0.00000828 AC XY: 6 AN XY: 724232

Gnomad4 AFR exome AF: 0.0000300

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000253

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000992

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152186 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74350

Gnomad4 AFR AF: 0.0000241

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000227

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

3-methylglutaconic aciduria with deafness, encephalopathy, and Leigh-like syndrome Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	3billion	Sep 01, 2022	The variant is observed at an extremely low frequency in the gnomAD v2.1.1 dataset (total allele frequency: <0.001%). Frameshift variant is predicted to result in a loss or disruption of normal protein function through nonsense-mediated decay (NMD) or protein truncation. Multiple pathogenic variants are reported downstream of the variant. The variant has been reported to be associated with SERAC1-related disorder (ClinVar ID: VCV000035558 / PMID: 22683713). Therefore, this variant is classified as Pathogenic according to the recommendation of ACMG/AMP guideline. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Feb 02, 2022	- -
Pathogenic, no assertion criteria provided	literature only	OMIM	Jun 10, 2012	- -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.97		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.71		Position offset: 0
DS_AL_spliceai		0.97		Position offset: 4

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

Publications

LitVar

Other links and lift over

dbSNP: rs772296795; hg19: chr6-158540198;