rs72549334

Variant summary

Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PS3PP3_StrongPP5_Very_Strong

The NM_001002294.3(FMO3):​c.1474C>T​(p.Arg492Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000281 in 1,613,882 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). ClinVar reports functional evidence for this variant: "SCV000351258: Functional studies indicated that the p.Arg492Trp variant severely attenuated the normal capacity of the enzyme to catalyze TMA N-oxidation, and that the variant protein was incapable of catalyzing the S-oxidation of methimazole (Dolphin et al. 2000). Additional functional studies by Yeung et al. (2007) found that the p.Arg492Trp variant was well expressed but failed to retain the FAD cofactor." and additional evidence is available in ClinVar.

Frequency

Genomes: 𝑓 0.00017 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00029 ( 1 hom. )

Consequence

FMO3
NM_001002294.3 missense

Scores

8
6
4

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: 0.150

Publications

22 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: Pathogenic. The variant received 16 ACMG points.

PS3
PS3 evidence extracted from ClinVar submissions: SCV000351258: Functional studies indicated that the p.Arg492Trp variant severely attenuated the normal capacity of the enzyme to catalyze TMA N-oxidation, and that the variant protein was incapable of catalyzing the S-oxidation of methimazole (Dolphin et al. 2000). Additional functional studies by Yeung et al. (2007) found that the p.Arg492Trp variant was well expressed but failed to retain the FAD cofactor.; SCV004354628: Experimental studies have shown that this missense change affects FMO3 function (PMID: 11191884, 17531949).
PP3
MetaRNN computational evidence supports a deleterious effect, 0.968
PP5
Variant 1-171117317-C-T is Pathogenic according to our data. Variant chr1-171117317-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 16309.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001002294.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
FMO3
NM_001002294.3
MANE Select
c.1474C>Tp.Arg492Trp
missense
Exon 9 of 9NP_001002294.1A0A024R8Z4
FMO3
NM_006894.6
c.1474C>Tp.Arg492Trp
missense
Exon 9 of 9NP_008825.4
FMO3
NM_001319173.2
c.1414C>Tp.Arg472Trp
missense
Exon 10 of 10NP_001306102.1

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
FMO3
ENST00000367755.9
TSL:1 MANE Select
c.1474C>Tp.Arg492Trp
missense
Exon 9 of 9ENSP00000356729.4P31513
FMO3
ENST00000896149.1
c.1474C>Tp.Arg492Trp
missense
Exon 9 of 9ENSP00000566208.1
FMO3
ENST00000896150.1
c.1474C>Tp.Arg492Trp
missense
Exon 10 of 10ENSP00000566209.1

Frequencies

GnomAD3 genomes
AF:
0.000171
AC:
26
AN:
152208
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000965
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
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:
0.000279
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.000124
AC:
31
AN:
251000
AF XY:
0.000118
show subpopulations
Gnomad AFR exome
AF:
0.000246
Gnomad AMR exome
AF:
0.0000579
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000220
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000292
AC:
427
AN:
1461674
Hom.:
1
Cov.:
32
AF XY:
0.000303
AC XY:
220
AN XY:
727104
show subpopulations
African (AFR)
AF:
0.000179
AC:
6
AN:
33472
American (AMR)
AF:
0.0000671
AC:
3
AN:
44710
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.0000504
AC:
2
AN:
39686
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53406
Middle Eastern (MID)
AF:
0.000173
AC:
1
AN:
5766
European-Non Finnish (NFE)
AF:
0.000366
AC:
407
AN:
1111858
Other (OTH)
AF:
0.000132
AC:
8
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.477
Heterozygous variant carriers
0
23
46
69
92
115
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
20
40
60
80
100
<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:
0.000171
AC:
26
AN:
152208
Hom.:
0
Cov.:
32
AF XY:
0.000121
AC XY:
9
AN XY:
74348
show subpopulations
African (AFR)
AF:
0.0000965
AC:
4
AN:
41462
American (AMR)
AF:
0.000131
AC:
2
AN:
15274
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000279
AC:
19
AN:
68038
Other (OTH)
AF:
0.000478
AC:
1
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.513
Heterozygous variant carriers
0
3
6
8
11
14
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:
0.000131
Hom.:
0
Bravo
AF:
0.000162
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.00104
AC:
4
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.000465
AC:
4
ExAC
AF:
0.000115
AC:
14
EpiCase
AF:
0.000436
EpiControl
AF:
0.000534

ClinVar

ClinVar submissions
Significance:Pathogenic/Likely pathogenic
Revision:criteria provided, multiple submitters, no conflicts
View on ClinVar
Pathogenic
VUS
Benign
Condition
4
-
-
Trimethylaminuria (4)
1
-
-
not provided (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.66
BayesDel_addAF
Uncertain
0.077
D
BayesDel_noAF
Pathogenic
0.17
CADD
Benign
23
DANN
Pathogenic
1.0
DEOGEN2
Benign
0.12
T
Eigen
Uncertain
0.51
Eigen_PC
Uncertain
0.33
FATHMM_MKL
Benign
0.69
D
LIST_S2
Uncertain
0.87
D
M_CAP
Benign
0.064
D
MetaRNN
Pathogenic
0.97
D
MetaSVM
Uncertain
0.19
D
MutationAssessor
Pathogenic
3.2
M
PhyloP100
0.15
PrimateAI
Benign
0.40
T
PROVEAN
Pathogenic
-6.8
D
REVEL
Uncertain
0.58
Sift
Pathogenic
0.0
D
Sift4G
Pathogenic
0.0
D
Polyphen
1.0
D
Vest4
0.94
MVP
0.82
MPC
0.068
ClinPred
0.55
D
GERP RS
3.3
Varity_R
0.73
gMVP
0.74
Mutation Taster
=1/99
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: rs72549334; hg19: chr1-171086457; COSMIC: COSV105288102; API
For research and educational, non-commercial use only. Not for clinical or diagnostic use. GeneBe does not provide medical advice. Data use for AI modeling is prohibited: if used, the cost is $0.001 per byte of downloaded uncompressed data.