2-27309916-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 4P and 2B. PM1 PM2 BP4_Moderate

The NM_002437.5(MPV17):c.527T>C(p.Leu176Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000026 in 1,613,602 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. L176L) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000027 (0 hom.)
• Consequence: MPV17 NM_002437.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.57

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM1: In a chain Protein Mpv17 (size 175) in uniprot entity MPV17_HUMAN there are 36 pathogenic changes around while only 6 benign (86%) in NM_002437.5
• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.12744331).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MPV17	NM_002437.5	c.527T>C	p.Leu176Pro	missense_variant	8/8	ENST00000380044.6
MPV17	XM_005264326.5	c.527T>C	p.Leu176Pro	missense_variant	8/8
MPV17	XM_017004151.2	c.479T>C	p.Leu160Pro	missense_variant	8/8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MPV17	ENST00000380044.6	c.527T>C	p.Leu176Pro	missense_variant	8/8	1	NM_002437.5	P1

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152200 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

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: 0.0000294

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000159 AC: 4 AN: 251136 Hom.: 0 AF XY: 0.0000221 AC XY: 3 AN XY: 135764

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 SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000352

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000274 AC: 40 AN: 1461402 Hom.: 0 Cov.: 30 AF XY: 0.0000234 AC XY: 17 AN XY: 727036

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: 0.0000342

Gnomad4 OTH exome AF: 0.0000331

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152200 Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1 AN XY: 74360

Gnomad4 AFR AF: 0.00

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: 0.0000294

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000227

ExAC AF: 0.0000247 AC: 3

EpiCase AF: 0.00

EpiControl AF: 0.0000593

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

Invitae

Sep 17, 2021

This sequence change replaces leucine with proline at codon 176 of the MPV17 protein (p.Leu176Pro). The leucine residue is weakly conserved and there is a moderate physicochemical difference between leucine and proline. This variant is present in population databases (rs779425887, ExAC 0.005%). This variant has not been reported in the literature in individuals with MPV17-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0". The proline amino acid residue is found in multiple mammalian species, suggesting that this missense change does not adversely affect protein function. These predictions have not been confirmed by published functional studies and their clinical significance is uncertain. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.30
BayesDel_addAF	Uncertain	0.025	T
BayesDel_noAF	Benign	-0.090
Cadd	Benign	19
Dann	Uncertain	0.99
DEOGEN2	Benign	0.15	T;T;T;T;T
Eigen	Benign	-0.49
Eigen_PC	Benign	-0.45
FATHMM_MKL	Uncertain	0.80	D
M_CAP	Benign	0.048	D
MetaRNN	Benign	0.13	T;T;T;T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	0.69	N;N;.;.;.
MutationTaster	Benign	0.96	D;D;D;D;D;D;D
PrimateAI	Uncertain	0.49	T
PROVEAN	Benign	-0.29	N;N;N;N;N
REVEL	Uncertain	0.40
Sift	Uncertain	0.0030	D;D;D;D;D
Sift4G	Uncertain	0.0080	D;D;D;D;D
Polyphen		0.0	B;B;.;.;.
Vest4		0.16
MutPred		0.45		Loss of stability (P = 0.0012);Loss of stability (P = 0.0012);.;.;.;
MVP		0.34
MPC		1.1
ClinPred		0.23	T
GERP RS		0.66
Varity_R		0.065
gMVP		0.53

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: rs779425887; hg19: chr2-27532784;