rs794726691

Variant names:

• chr17-16006489-TGCTG-T
• rs794726691
• NM_017775.4:c.601_604delGGCT

Variant summary

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

The NM_017775.4(TTC19):​c.601_604delGGCT​(p.Gly201MetfsTer8) variant causes a frameshift change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: TTC19 NM_017775.4 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 5.86
• Publications: 2 publications found

Genes affected

TTC19 (HGNC:26006): (tetratricopeptide repeat domain 19) This gene encodes a protein with a tetratricopeptide repeat (TPR) domain containing several TPRs of about 34 aa each. These repeats are found in a variety of organisms including bacteria, fungi and plants, and are involved in a variety of functions including protein-protein interactions. This protein is embedded in the inner mitochondrial membrane and is involved in the formation of the mitochondrial respiratory chain III. It has also been suggested that this protein plays a role in cytokinesis. Mutations in this gene cause mitochondrial complex III deficiency. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Sep 2012]

TTC19 Gene-Disease associations (from GenCC):

• Leigh syndrome

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• mitochondrial complex III deficiency nuclear type 2

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Genomics England PanelApp, Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P
• mitochondrial disease

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• mitochondrial complex III deficiency

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 18 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
• PP5: Variant 17-16006489-TGCTG-T is Pathogenic according to our data. Variant chr17-16006489-TGCTG-T is described in ClinVar as Pathogenic. ClinVar VariationId is 102437.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_017775.4. 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
	TTC19	NM_017775.4	MANE Select	c.601_604delGGCT	p.Gly201MetfsTer8	frameshift	Exon 7 of 10	NP_060245.3
	TTC19	NM_001271420.2		c.280_283delGGCT	p.Gly94MetfsTer8	frameshift	Exon 7 of 10	NP_001258349.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TTC19	ENST00000261647.10	TSL:1 MANE Select	c.601_604delGGCT	p.Gly201MetfsTer8	frameshift	Exon 7 of 10	ENSP00000261647.5	Q6DKK2
	TTC19	ENST00000873205.1		c.718_721delGGCT	p.Gly240MetfsTer8	frameshift	Exon 7 of 10	ENSP00000543264.1
	TTC19	ENST00000873204.1		c.616_619delGGCT	p.Gly206MetfsTer8	frameshift	Exon 7 of 10	ENSP00000543263.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251456 AF XY: 0.00000736

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: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 0.00000205 AC: 3 AN: 1460142 Hom.: 0 AF XY: 0.00000275 AC XY: 2 AN XY: 726516

African (AFR) AF: 0.00 AC: 0 AN: 33458

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26122

East Asian (EAS) AF: 0.00 AC: 0 AN: 39684

South Asian (SAS) AF: 0.00 AC: 0 AN: 86218

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53418

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5590

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1110620

Other (OTH) AF: 0.00 AC: 0 AN: 60310

GnomAD4 genome Cov.: 33

Alfa AF: 0.0000508 Hom.: 0

Bravo AF: 0.00000756

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
3	-	-	not provided (3)
1	-	-	Mitochondrial complex III deficiency nuclear type 2 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		5.9
Mutation Taster		=2/198	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		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: rs794726691; hg19: chr17-15909803;