14-64449512-G-A

Position:

• chr14-64449512-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_005956.4(MTHFD1):​c.2347G>A​(p.Val783Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000684 in 1,461,846 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. V783V) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000068 (0 hom.)
• Consequence: MTHFD1 NM_005956.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 8.13

Genes affected

MTHFD1 (HGNC:7432): (methylenetetrahydrofolate dehydrogenase, cyclohydrolase and formyltetrahydrofolate synthetase 1) This gene encodes a protein that possesses three distinct enzymatic activities, 5,10-methylenetetrahydrofolate dehydrogenase, 5,10-methenyltetrahydrofolate cyclohydrolase and 10-formyltetrahydrofolate synthetase. Each of these activities catalyzes one of three sequential reactions in the interconversion of 1-carbon derivatives of tetrahydrofolate, which are substrates for methionine, thymidylate, and de novo purine syntheses. The trifunctional enzymatic activities are conferred by two major domains, an aminoterminal portion containing the dehydrogenase and cyclohydrolase activities and a larger synthetase domain. [provided by RefSeq, Jul 2008]

ZBTB25 (HGNC:13112): (zinc finger and BTB domain containing 25) Predicted to enable DNA-binding transcription repressor activity, RNA polymerase II-specific and RNA polymerase II cis-regulatory region sequence-specific DNA binding activity. Predicted to be involved in regulation of transcription by RNA polymerase II. Located in nucleoplasm. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.792

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MTHFD1	NM_005956.4	c.2347G>A	p.Val783Met	missense_variant	24/28	ENST00000652337.1
MTHFD1	NM_001364837.1	c.2347G>A	p.Val783Met	missense_variant	24/27
ZBTB25	NM_001304508.1	c.*39C>T		3_prime_UTR_variant	3/3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MTHFD1	ENST00000652337.1	c.2347G>A	p.Val783Met	missense_variant	24/28		NM_005956.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251152 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135744

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: 0.00000881

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000684 AC: 10 AN: 1461846 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727228

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000540

Gnomad4 OTH exome AF: 0.0000497

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000330 Hom.: 0

Bravo AF: 0.0000113

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 07, 2022

The c.2347G>A (p.V783M) alteration is located in exon 24 (coding exon 24) of the MTHFD1 gene. This alteration results from a G to A substitution at nucleotide position 2347, causing the valine (V) at amino acid position 783 to be replaced by a methionine (M). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Apr 06, 2022

This sequence change replaces valine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 783 of the MTHFD1 protein (p.Val783Met). This variant is present in population databases (no rsID available, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with MTHFD1-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). 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	0.22
BayesDel_addAF	Pathogenic	0.17	D
BayesDel_noAF	Uncertain	0.010
CADD	Pathogenic	28
DANN	Pathogenic	1.0
Eigen	Pathogenic	0.97
Eigen_PC	Pathogenic	0.91
FATHMM_MKL	Pathogenic	0.99	D
M_CAP	Benign	0.049	D
MetaRNN	Pathogenic	0.79	D;D
MetaSVM	Benign	-0.47	T
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Uncertain	0.70	T
PROVEAN	Uncertain	-2.7	D;.
REVEL	Uncertain	0.40
Sift	Pathogenic	0.0	D;.
Sift4G	Uncertain	0.0030	D;D
Polyphen		1.0	D;.
Vest4		0.70
MVP		0.61
MPC		1.1
ClinPred		0.99	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

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: rs1029133044; hg19: chr14-64916230; COSMIC: COSV53703111; COSMIC: COSV53703111;