rs72549332

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PP5_Moderate

The NM_001002294.3(FMO3):​c.1302G>A​(p.Met434Ile) variant causes a missense change. The variant allele was found at a frequency of 0.000118 in 1,614,010 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★).

Frequency

Genomes: 𝑓 0.000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00012 ( 0 hom. )

Consequence

FMO3
NM_001002294.3 missense

Scores

2
4
13

Clinical Significance

Likely pathogenic criteria provided, single submitter P:2

Conservation

PhyloP100: 5.89

Publications

7 publications found
Variant links:
Genes affected
FMO3 (HGNC:3771): (flavin containing dimethylaniline monoxygenase 3) Flavin-containing monooxygenases (FMO) are an important class of drug-metabolizing enzymes that catalyze the NADPH-dependent oxygenation of various nitrogen-,sulfur-, and phosphorous-containing xenobiotics such as therapeutic drugs, dietary compounds, pesticides, and other foreign compounds. The human FMO gene family is composed of 5 genes and multiple pseudogenes. FMO members have distinct developmental- and tissue-specific expression patterns. The expression of this FMO3 gene, the major FMO expressed in adult liver, can vary up to 20-fold between individuals. This inter-individual variation in FMO3 expression levels is likely to have significant effects on the rate at which xenobiotics are metabolised and, therefore, is of considerable interest to the pharmaceutical industry. This transmembrane protein localizes to the endoplasmic reticulum of many tissues. Alternative splicing of this gene results in multiple transcript variants encoding different isoforms. Mutations in this gene cause the disorder trimethylaminuria (TMAu) which is characterized by the accumulation and excretion of unmetabolized trimethylamine and a distinctive body odor. In healthy individuals, trimethylamine is primarily converted to the non odorous trimethylamine N-oxide.[provided by RefSeq, Jan 2016]
FMO3 Gene-Disease associations (from GenCC):
  • trimethylaminuria
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • severe primary trimethylaminuria
    Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PP5
Variant 1-171117145-G-A is Pathogenic according to our data. Variant chr1-171117145-G-A is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 16314.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FMO3NM_001002294.3 linkc.1302G>A p.Met434Ile missense_variant Exon 9 of 9 ENST00000367755.9 NP_001002294.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FMO3ENST00000367755.9 linkc.1302G>A p.Met434Ile missense_variant Exon 9 of 9 1 NM_001002294.3 ENSP00000356729.4

Frequencies

GnomAD3 genomes
AF:
0.0000657
AC:
10
AN:
152206
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.000132
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000558
AC:
14
AN:
251112
AF XY:
0.000103
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:
0.0000353
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000124
AC:
181
AN:
1461804
Hom.:
0
Cov.:
32
AF XY:
0.000139
AC XY:
101
AN XY:
727202
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.00
AC:
0
AN:
44718
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39696
South Asian (SAS)
AF:
0.000336
AC:
29
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.000134
AC:
149
AN:
1111952
Other (OTH)
AF:
0.0000497
AC:
3
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.473
Heterozygous variant carriers
0
10
19
29
38
48
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<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:
0.0000657
AC:
10
AN:
152206
Hom.:
0
Cov.:
32
AF XY:
0.0000403
AC XY:
3
AN XY:
74358
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41450
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000132
AC:
9
AN:
68042
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.0000900
Hom.:
0
Bravo
AF:
0.0000302
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000259
AC:
1
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000659
AC:
8
EpiCase
AF:
0.0000545
EpiControl
AF:
0.000178

ClinVar

Significance: Likely pathogenic
Submissions summary: Pathogenic:2
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not provided Pathogenic:1
Jan 30, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces methionine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 434 of the FMO3 protein (p.Met434Ile). This variant is present in population databases (rs72549332, gnomAD 0.03%). This missense change has been observed in individual(s) with trimethylaminuria (PMID: 8401051, 11191884). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 16314). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on FMO3 protein function. Experimental studies have shown that this missense change affects FMO3 function (PMID: 11191884). In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Trimethylaminuria Pathogenic:1
Dec 01, 2000
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.72
BayesDel_addAF
Benign
-0.073
T
BayesDel_noAF
Uncertain
-0.040
CADD
Benign
20
DANN
Uncertain
0.98
DEOGEN2
Benign
0.039
T
Eigen
Benign
0.095
Eigen_PC
Benign
0.18
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Benign
0.68
T
M_CAP
Benign
0.012
T
MetaRNN
Benign
0.19
T
MetaSVM
Benign
-0.98
T
MutationAssessor
Uncertain
2.6
M
PhyloP100
5.9
PrimateAI
Benign
0.43
T
PROVEAN
Benign
-2.2
N
REVEL
Benign
0.26
Sift
Benign
0.11
T
Sift4G
Uncertain
0.058
T
Polyphen
0.010
B
Vest4
0.24
MutPred
0.88
Loss of phosphorylation at Y433 (P = 0.0818);
MVP
0.47
MPC
0.15
ClinPred
0.24
T
GERP RS
4.4
Varity_R
0.42
gMVP
0.71
Mutation Taster
=0/100
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.29
Details are displayed if max score is > 0.2
DS_AL_spliceai
0.29
Position offset: -45

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs72549332; hg19: chr1-171086285; COSMIC: COSV63007304; API