rs377656387

Positions:

• chr4-158706351-C-A
• chr4-158706351-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM2 PM5 PP3_Strong

The NM_004453.4(ETFDH):​c.1448C>A​(p.Pro483Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic 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. P483L) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: ETFDH NM_004453.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.91

Genes affected

ETFDH (HGNC:3483): (electron transfer flavoprotein dehydrogenase) This gene encodes a component of the electron-transfer system in mitochondria and is essential for electron transfer from a number of mitochondrial flavin-containing dehydrogenases to the main respiratory chain. Mutations in this gene are associated with glutaric acidemia. Alternatively spliced transcript variants that encode distinct isoforms have been observed. [provided by RefSeq, Aug 2013]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr4-158706351-C-T is described in Lovd as [Likely_pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.968

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
ETFDH	NM_004453.4	c.1448C>A	p.Pro483Gln	missense_variant	11/13	ENST00000511912.6	NP_004444.2
ETFDH	NM_001281737.2	c.1307C>A	p.Pro436Gln	missense_variant	10/12		NP_001268666.1
ETFDH	NM_001281738.1	c.1265C>A	p.Pro422Gln	missense_variant	9/11		NP_001268667.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ETFDH	ENST00000511912.6	c.1448C>A	p.Pro483Gln	missense_variant	11/13	1	NM_004453.4	ENSP00000426638	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

May 14, 2024

Variant summary: ETFDH c.1448C>A (p.Pro483Gln) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 251258 control chromosomes. c.1448C>A has been reported in the literature in at least one compound heterozygous individual affected with late-onset Glutaric Aciduria, Type 2 (e.g. Zhu_2023). These data are not sufficient alone to allow any conclusion about variant significance. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. A different variant located at the same codon (c.1448C>T, p.Pro483Leu) has been classified as pathogenic, supporting a critical relevance of this residue to ETFDH protein function. The following publication has been ascertained in the context of this evaluation (PMID: 36779069). No submitters have cited clinical-significance assessments for this variant to ClinVar. Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.65
BayesDel_addAF	Pathogenic	0.50	D
BayesDel_noAF	Pathogenic	0.49
CADD	Pathogenic	28
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.80	D;.
Eigen	Pathogenic	0.95
Eigen_PC	Pathogenic	0.85
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D;D
M_CAP	Pathogenic	0.81	D
MetaRNN	Pathogenic	0.97	D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.5	H;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.64	T
PROVEAN	Pathogenic	-7.4	D;D
REVEL	Pathogenic	0.96
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;.
Vest4		0.89
MutPred		0.79		Gain of MoRF binding (P = 0.0362);.;
MVP		0.98
MPC		0.48
ClinPred		0.99	D
GERP RS		5.0
Varity_R		0.86
gMVP		0.90

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

Publications

LitVar

Other links and lift over

dbSNP: rs377656387; hg19: chr4-159627503;