chr2-27312685-CCAA-C

Variant names:

• chr2-27312685-CCAA-C
• rs267607264
• NM_002437.5:c.271_273delTTG

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1 PM2 PM4_Supporting PP5

The NM_002437.5(MPV17):​c.271_273delTTG​(p.Leu91del) variant causes a conservative inframe deletion change. The variant allele was found at a frequency of 0.0000112 in 1,614,102 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. L91L) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000010 (0 hom.)
• Consequence: MPV17 NM_002437.5 conservative_inframe_deletion
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:6 U:1
• Conservation: PhyloP100: 5.11
• Publications: 3 publications found

Genes affected

MPV17 (HGNC:7224): (mitochondrial inner membrane protein MPV17) This gene encodes a mitochondrial inner membrane protein that is implicated in the metabolism of reactive oxygen species. Mutations in this gene have been associated with the hepatocerebral form of mitochondrial DNA depletion syndrome (MDDS). [provided by RefSeq, Jul 2008]

MPV17 Gene-Disease associations (from GenCC):

• mitochondrial disease

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• mitochondrial DNA depletion syndrome 6 (hepatocerebral type)

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
• Charcot-Marie-Tooth disease, axonal, type 2EE

  Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM1: In a hotspot region, there are 8 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 11 uncertain in NM_002437.5
• PM2: Very rare variant in population databases, with high coverage
• PM4: Nonframeshift variant in NON repetitive region in NM_002437.5. Strenght limited to Supporting due to length of the change: 1aa.
• PP5: Variant 2-27312685-CCAA-C is Pathogenic according to our data. Variant chr2-27312685-CCAA-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 38353.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_002437.5. 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
	MPV17	NM_002437.5	MANE Select	c.271_273delTTG	p.Leu91del	conservative_inframe_deletion	Exon 4 of 8	NP_002428.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MPV17	ENST00000380044.6	TSL:1 MANE Select	c.271_273delTTG	p.Leu91del	conservative_inframe_deletion	Exon 4 of 8	ENSP00000369383.1
	MPV17	ENST00000233545.6	TSL:1	c.271_273delTTG	p.Leu91del	conservative_inframe_deletion	Exon 3 of 7	ENSP00000233545.2
	MPV17	ENST00000403262.6	TSL:1	c.271_273delTTG	p.Leu91del	conservative_inframe_deletion	Exon 4 of 8	ENSP00000385671.1

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152248 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000482

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000199 AC: 5 AN: 251476 AF XY: 0.0000221

Gnomad AFR exome AF: 0.000123

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: 0.0000264

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000103 AC: 15 AN: 1461854 Hom.: 0 AF XY: 0.00000550 AC XY: 4 AN XY: 727236

African (AFR) AF: 0.000179 AC: 6 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44720

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.0000252 AC: 1 AN: 39700

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86252

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53408

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000629 AC: 7 AN: 1111996

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152248 Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1 AN XY: 74374

African (AFR) AF: 0.0000482 AC: 2 AN: 41462

American (AMR) AF: 0.00 AC: 0 AN: 15290

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5192

South Asian (SAS) AF: 0.00 AC: 0 AN: 4836

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10630

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68046

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.0000712 Hom.: 0

Bravo AF: 0.0000340

ClinVar

ClinVar submissions as Germline

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
2	1	-	not provided (3)
1	-	-	Charcot-Marie-Tooth disease, axonal, type 2EE (1)
1	-	-	Mitochondrial DNA depletion syndrome (1)
1	-	-	Mitochondrial DNA depletion syndrome 6 (hepatocerebral type) (1)
1	-	-	Mitochondrial DNA depletion syndrome 6 (hepatocerebral type);C5193076:Charcot-Marie-Tooth disease, axonal, type 2EE (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		5.1
Mutation Taster		=52/48	disease causing (ClinVar)

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: rs267607264; hg19: chr2-27535552;