chr5-61073136-C-A

Variant names:

• chr5-61073136-C-A
• rs137852863
• NM_174889.5:c.139C>A

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2 BP4 BP7

The NM_174889.5(NDUFAF2):​c.139C>A​(p.Arg47Arg) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000686 in 1,457,178 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: NDUFAF2 NM_174889.5 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.860
• Publications: 0 publications found

Genes affected

NDUFAF2 (HGNC:28086): (NADH:ubiquinone oxidoreductase complex assembly factor 2) NADH:ubiquinone oxidoreductase (complex I) catalyzes the transfer of electrons from NADH to ubiquinone (coenzyme Q) in the first step of the mitochondrial respiratory chain, resulting in the translocation of protons across the inner mitochondrial membrane. This gene encodes a complex I assembly factor. Mutations in this gene cause progressive encephalopathy resulting from mitochondrial complex I deficiency. [provided by RefSeq, Jul 2008]

NDUFAF2 Gene-Disease associations (from GenCC):

• Leigh syndrome

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: ClinGen, G2P
• mitochondrial complex I deficiency, nuclear type 10

  Inheritance: AR Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
• Leigh syndrome with leukodystrophy

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• mitochondrial complex I deficiency

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (REVEL=0.222).
• BP7: Synonymous conserved (PhyloP=0.86 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NDUFAF2	NM_174889.5	c.139C>A	p.Arg47Arg	synonymous_variant	Exon 2 of 4	ENST00000296597.10	NP_777549.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NDUFAF2	ENST00000296597.10	c.139C>A	p.Arg47Arg	synonymous_variant	Exon 2 of 4	1	NM_174889.5	ENSP00000296597.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.86e-7 AC: 1 AN: 1457178 Hom.: 0 Cov.: 29 AF XY: 0.00000138 AC XY: 1 AN XY: 725220

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33382

American (AMR) AF: 0.00 AC: 0 AN: 44714

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26080

East Asian (EAS) AF: 0.00 AC: 0 AN: 39542

South Asian (SAS) AF: 0.00 AC: 0 AN: 86150

European-Finnish (FIN) AF: 0.0000188 AC: 1 AN: 53198

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5688

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1108236

Other (OTH) AF: 0.00 AC: 0 AN: 60188

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.26
CADD	Benign	13
DANN	Benign	0.67
PhyloP100		0.86

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: rs137852863; hg19: chr5-60368963;