1-171103834-A-G

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM2PM5PP3PP5_Moderate

The NM_001002294.3(FMO3):​c.182A>G​(p.Asn61Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000198 in 1,613,632 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 Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N61K) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000021 ( 0 hom. )

Consequence

FMO3
NM_001002294.3 missense

Scores

7
8
4

Clinical Significance

Likely pathogenic criteria provided, single submitter P:2O:1

Conservation

PhyloP100: 9.25
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr1-171103835-C-A is described in Lovd as [Pathogenic].
PP3
MetaRNN computational evidence supports a deleterious effect, 0.834
PP5
Variant 1-171103834-A-G is Pathogenic according to our data. Variant chr1-171103834-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 16313.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-171103834-A-G is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FMO3NM_001002294.3 linkc.182A>G p.Asn61Ser missense_variant Exon 3 of 9 ENST00000367755.9 NP_001002294.1 P31513A0A024R8Z4Q53FW5

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FMO3ENST00000367755.9 linkc.182A>G p.Asn61Ser missense_variant Exon 3 of 9 1 NM_001002294.3 ENSP00000356729.4 P31513
FMO3ENST00000479749.1 linkc.182A>G p.Asn61Ser missense_variant Exon 3 of 6 5 ENSP00000477451.1 V9GZ60

Frequencies

GnomAD3 genomes
AF:
0.0000132
AC:
2
AN:
151992
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:
0.000208
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000159
AC:
4
AN:
251252
Hom.:
0
AF XY:
0.0000221
AC XY:
3
AN XY:
135778
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 SAS exome
AF:
0.0000653
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000205
AC:
30
AN:
1461640
Hom.:
0
Cov.:
31
AF XY:
0.0000151
AC XY:
11
AN XY:
727126
show subpopulations
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:
0.0000270
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000132
AC:
2
AN:
151992
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74228
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.000208
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000211
Hom.:
0
Bravo
AF:
0.0000113
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Likely pathogenic
Submissions summary: Pathogenic:2Other:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Trimethylaminuria Pathogenic:2Other:1
Aug 07, 2023
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: FMO3 c.182A>G (p.Asn61Ser) results in a 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 1.6e-05 in 251252 control chromosomes (gnomAD). c.182A>G has been reported in the literature in individuals affected with Trimethylaminuria who had another missense variant in trans that some ClinVar submitters have classified as pathogenic (Dolphin_2000). These data indicate that the variant may be associated with disease. Publications report experimental evidence evaluating an impact on protein function, finding a variant effect resulting in <10% of normal trimethylamine metabolism and NADPH binding affinity (Dolphin_2000, Yeung_2007, Gao_2017). The following publications have been ascertained in the context of this evaluation (PMID: 29116146, 31580948, 11191884, 17531949). No submitters have cited clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as likely pathogenic. -

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

- -

-
GeneReviews
Significance: not provided
Review Status: no classification provided
Collection Method: literature only

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.44
BayesDel_addAF
Benign
-0.14
T
BayesDel_noAF
Benign
-0.25
CADD
Pathogenic
27
DANN
Uncertain
1.0
DEOGEN2
Benign
0.12
T;T
Eigen
Pathogenic
0.80
Eigen_PC
Uncertain
0.65
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Pathogenic
0.99
D;D
M_CAP
Uncertain
0.17
D
MetaRNN
Pathogenic
0.83
D;D
MetaSVM
Uncertain
0.050
D
MutationAssessor
Pathogenic
4.6
H;.
PrimateAI
Uncertain
0.53
T
PROVEAN
Pathogenic
-4.7
D;.
REVEL
Uncertain
0.57
Sift
Pathogenic
0.0
D;.
Sift4G
Uncertain
0.0020
D;D
Polyphen
1.0
D;.
Vest4
0.89
MVP
0.82
MPC
0.24
ClinPred
0.99
D
GERP RS
3.5
Varity_R
0.91
gMVP
0.84

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.39
Details are displayed if max score is > 0.2
DS_AG_spliceai
0.39
Position offset: 1
DS_AL_spliceai
0.22
Position offset: -49

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs72549322; hg19: chr1-171072975; API