chr1-171092803-T-C

Variant names:

• chr1-171092803-T-C
• rs371276117
• NM_001002294.3:c.132+13T>C

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_Strong BP6

The NM_001002294.3(FMO3):​c.132+13T>C variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000155 in 1,613,428 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 Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000014 (0 hom.)
• Consequence: FMO3 NM_001002294.3 intron
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:1
• Conservation: PhyloP100: 0.147
• Publications: 0 publications found

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)

FMO1-AS1 (HGNC:40240):

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.86).
• BP6: Variant 1-171092803-T-C is Benign according to our data. Variant chr1-171092803-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 874915.

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.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FMO3	NM_001002294.3	MANE Select	c.132+13T>C		intron	N/A	NP_001002294.1	A0A024R8Z4
	FMO3	NM_006894.6		c.132+13T>C		intron	N/A	NP_008825.4
	FMO3	NM_001319173.2		c.-56+13T>C		intron	N/A	NP_001306102.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FMO3	ENST00000367755.9	TSL:1 MANE Select	c.132+13T>C		intron	N/A	ENSP00000356729.4	P31513
	FMO3	ENST00000479749.1	TSL:5	c.132+13T>C		intron	N/A	ENSP00000477451.1	V9GZ60
	FMO3	ENST00000534514.1	TSL:1	n.215+13T>C		intron	N/A

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152146 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000966

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: 0.00

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00000796 AC: 2 AN: 251142 AF XY: 0.00

Gnomad AFR exome AF: 0.000123

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: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000144 AC: 21 AN: 1461282 Hom.: 0 Cov.: 31 AF XY: 0.0000110 AC XY: 8 AN XY: 726948

African (AFR) AF: 0.000299 AC: 10 AN: 33468

American (AMR) AF: 0.0000224 AC: 1 AN: 44678

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26122

East Asian (EAS) AF: 0.00 AC: 0 AN: 39688

South Asian (SAS) AF: 0.00 AC: 0 AN: 86226

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53392

Middle Eastern (MID) AF: 0.000359 AC: 2 AN: 5568

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111782

Other (OTH) AF: 0.0000994 AC: 6 AN: 60358

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152146 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74308

African (AFR) AF: 0.0000966 AC: 4 AN: 41426

American (AMR) AF: 0.00 AC: 0 AN: 15266

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5182

South Asian (SAS) AF: 0.00 AC: 0 AN: 4832

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10630

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68022

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.0000434 Hom.: 0

Bravo AF: 0.0000340

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	-	1	not provided (1)
-	1	-	Trimethylaminuria (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.86
CADD	Benign	2.4
DANN	Benign	0.40
PhyloP100		0.15

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

Other links and lift over

dbSNP: rs371276117; hg19: chr1-171061944;