rs1057519360

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2PP3PP5

The NM_005957.5(MTHFR):​c.416C>T​(p.Thr139Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000173 in 1,614,054 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 Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. T139T) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000018 ( 0 hom. )

Consequence

MTHFR
NM_005957.5 missense

Scores

4
10
5

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:4U:1

Conservation

PhyloP100: 7.27

Publications

5 publications found
Variant links:
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]
MTHFR Gene-Disease associations (from GenCC):
  • homocystinuria due to methylene tetrahydrofolate reductase deficiency
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), G2P, ClinGen, Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.77
PP5
Variant 1-11801220-G-A is Pathogenic according to our data. Variant chr1-11801220-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 222893.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MTHFRNM_005957.5 linkc.416C>T p.Thr139Met missense_variant Exon 3 of 12 ENST00000376590.9 NP_005948.3 P42898-1Q8IU67Q59GJ6

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MTHFRENST00000376590.9 linkc.416C>T p.Thr139Met missense_variant Exon 3 of 12 1 NM_005957.5 ENSP00000365775.3 P42898-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152204
Hom.:
0
Cov.:
32
show subpopulations
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
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251418
AF XY:
0.00000736
show subpopulations
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000185
AC:
27
AN:
1461850
Hom.:
0
Cov.:
31
AF XY:
0.0000234
AC XY:
17
AN XY:
727222
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86254
European-Finnish (FIN)
AF:
0.0000375
AC:
2
AN:
53402
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5758
European-Non Finnish (NFE)
AF:
0.0000189
AC:
21
AN:
1112010
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60388
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.501
Heterozygous variant carriers
0
2
4
6
8
10
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152204
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74340
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
41448
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5206
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10612
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68036
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000189
EpiCase
AF:
0.000109
EpiControl
AF:
0.00

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:4Uncertain:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Homocystinuria due to methylene tetrahydrofolate reductase deficiency Pathogenic:2Uncertain:1
Jan 14, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: MTHFR c.416C>T (p.Thr139Met) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 4e-06 in 251418 control chromosomes. c.416C>T has been reported in the literature in individuals affected with Homocystinuria Due To Methylene Tetrahydrofolate Reductase Deficiency (Yano_2004, Liu_2024). These data indicate that the variant may be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein function. The most pronounced variant effect results in 10%-<30% of normal activity (Yano_2004). The following publications have been ascertained in the context of this evaluation (PMID: 15048559, 37972026). ClinVar contains an entry for this variant (Variation ID: 222893). Based on the evidence outlined above, the variant was classified as likely pathogenic. -

Aug 31, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces threonine with methionine at codon 139 of the MTHFR protein (p.Thr139Met). The threonine residue is moderately conserved and there is a moderate physicochemical difference between threonine and methionine. This variant is not present in population databases (ExAC no frequency). This missense change has been observed in individual(s) with severe MTHFR deficiency (PMID: 15048559). ClinVar contains an entry for this variant (Variation ID: 222893). 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: "Possibly Damaging"; Align-GVGD: "Class C0"). Experimental studies have shown that this missense change affects MTHFR function (PMID: 15048559). 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. -

-
University Children's Hospital, University of Zurich
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Schizophrenia;C1856061:Homocystinuria due to methylene tetrahydrofolate reductase deficiency;C1866558:Neural tube defects, folate-sensitive;C3160733:Thrombophilia due to thrombin defect Pathogenic:1
Jan 09, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Neural tube defects, folate-sensitive Pathogenic:1
Nov 27, 2023
Baylor Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.16
BayesDel_addAF
Pathogenic
0.23
D
BayesDel_noAF
Uncertain
0.090
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.80
D;.;.;D;.;.;.;.
Eigen
Uncertain
0.58
Eigen_PC
Uncertain
0.64
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Uncertain
0.92
.;D;.;D;D;D;D;D
M_CAP
Uncertain
0.12
D
MetaRNN
Pathogenic
0.77
D;D;D;D;D;D;D;D
MetaSVM
Uncertain
0.62
D
MutationAssessor
Uncertain
2.2
M;.;.;M;.;.;.;.
PhyloP100
7.3
PrimateAI
Uncertain
0.54
T
PROVEAN
Benign
-1.8
N;N;N;N;.;.;.;N
REVEL
Pathogenic
0.67
Sift
Benign
0.092
T;D;D;T;.;.;.;D
Sift4G
Benign
0.12
T;T;T;T;.;.;.;.
Polyphen
0.82
P;.;.;P;.;.;.;.
Vest4
0.83
MutPred
0.50
Gain of MoRF binding (P = 0.09);.;.;Gain of MoRF binding (P = 0.09);.;Gain of MoRF binding (P = 0.09);Gain of MoRF binding (P = 0.09);Gain of MoRF binding (P = 0.09);
MVP
0.98
MPC
0.84
ClinPred
0.81
D
GERP RS
5.7
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.27
gMVP
0.78
Mutation Taster
=2/98
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs1057519360; hg19: chr1-11861277; COSMIC: COSV106415975; COSMIC: COSV106415975; API