chr8-73976305-C-A

Position:

• chr8-73976305-C-A

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_017866.6(TMEM70):​c.24C>A​(p.Ser8Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000206 in 1,600,778 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. S8P) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000022 (0 hom.)
• Consequence: TMEM70 NM_017866.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.515

Genes affected

TMEM70 (HGNC:26050): (transmembrane protein 70) This gene likely encodes a mitochondrial membrane protein. The encoded protein may play a role in biogenesis of mitochondrial ATP synthase. Mutations in this gene have been associated with neonatal mitochondrial encephalocardiomyopathy due to ATP synthase deficiency. Alternatively spliced transcript variants have been described. [provided by RefSeq, Feb 2010]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.054804593).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TMEM70	NM_017866.6	c.24C>A	p.Ser8Arg	missense_variant	1/3	ENST00000312184.6
TMEM70	NM_001040613.3	c.24C>A	p.Ser8Arg	missense_variant	1/3
TMEM70	NR_033334.2	n.111C>A		non_coding_transcript_exon_variant	1/4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TMEM70	ENST00000312184.6	c.24C>A	p.Ser8Arg	missense_variant	1/3	1	NM_017866.6	P1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152220 Hom.: 0 Cov.: 33

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.0000221 AC: 32 AN: 1448558 Hom.: 0 Cov.: 32 AF XY: 0.0000222 AC XY: 16 AN XY: 721186

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: 0.0000288

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152220 Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1 AN XY: 74370

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: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Mitochondrial complex V (ATP synthase) deficiency nuclear type 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 03, 2022

This sequence change replaces serine, which is neutral and polar, with arginine, which is basic and polar, at codon 8 of the TMEM70 protein (p.Ser8Arg). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with TMEM70-related conditions. ClinVar contains an entry for this variant (Variation ID: 1408668). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The arginine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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	0.14
BayesDel_addAF	Benign	-0.33	T
BayesDel_noAF	Benign	-0.72
CADD	Benign	11
DANN	Benign	0.67
DEOGEN2	Benign	0.00054	.;T
Eigen	Benign	-1.1
Eigen_PC	Benign	-1.0
FATHMM_MKL	Benign	0.24	N
LIST_S2	Benign	0.23	T;T
M_CAP	Benign	0.015	T
MetaRNN	Benign	0.055	T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.14	N;N
MutationTaster	Benign	1.0	N;N
PrimateAI	Uncertain	0.58	T
PROVEAN	Benign	-0.17	N;N
REVEL	Benign	0.029
Sift	Benign	0.24	T;T
Sift4G	Benign	0.42	T;T
Polyphen		0.0	.;B
Vest4		0.085
MutPred		0.37		Loss of sheet (P = 0.0357);Loss of sheet (P = 0.0357);
MVP		0.072
MPC		0.25
ClinPred		0.095	T
GERP RS		2.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.070
gMVP		0.26

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: rs1215450178; hg19: chr8-74888540;