rs1553188112

chr1-11803155-CAG-C

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The ENST00000376592.6(MTHFR):c.-41_-40del variant causes a 5 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000709 in 1,409,472 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 7.1e-7 (0 hom.)
• Consequence: MTHFR ENST00000376592.6 5_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter P:1 U:1
• Conservation: PhyloP100: 1.45

Genes affected

MTHFR (HGNC:7436): (methylenetetrahydrofolate reductase) The protein encoded by this gene catalyzes the conversion of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate, a co-substrate for homocysteine remethylation to methionine. Genetic variation in this gene influences susceptibility to occlusive vascular disease, neural tube defects, colon cancer and acute leukemia, and mutations in this gene are associated with methylenetetrahydrofolate reductase deficiency.[provided by RefSeq, Oct 2009]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MTHFR	NM_005957.5	c.-13-28_-13-27del		intron_variant		ENST00000376590.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MTHFR	ENST00000376590.9	c.-13-28_-13-27del		intron_variant		1	NM_005957.5	A1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 7.09e-7 AC: 1 AN: 1409472 Hom.: 0 AF XY: 0.00000144 AC XY: 1 AN XY: 696420

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: 9.23e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Homocystinuria due to methylene tetrahydrofolate reductase deficiency Pathogenic:1 Uncertain:1

Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Jan 13, 2022	This sequence change falls in intron 1 of the MTHFR gene. It does not directly change the encoded amino acid sequence of the MTHFR protein. 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. Experimental studies and prediction algorithms are not available or were not evaluated, and the effect of this variant on mRNA splicing is currently unknown. ClinVar contains an entry for this variant (Variation ID: 187865). This variant is also known as c.-40_-41delTC. This variant has been observed in individual(s) with methylenetetrahydrofolate reductase deficiency (PMID: 25736335). This variant is not present in population databases (gnomAD no frequency). -
Pathogenic, no assertion criteria provided	clinical testing	University Children's Hospital, University of Zurich	-	- -

Computational scores

Source: dbNSFP v4.3

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: rs1553188112; hg19: chr1-11863212;