rs774358971

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 3P and 4B. PM1PP3BS2

The NM_144997.7(FLCN):​c.535C>T​(p.Arg179Trp) variant causes a missense change. The variant allele was found at a frequency of 0.0000446 in 1,613,546 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R179G) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000048 ( 1 hom. )

Consequence

FLCN
NM_144997.7 missense

Scores

12
6
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7B:2

Conservation

PhyloP100: 4.18

Publications

2 publications found
Variant links:
Genes affected
FLCN (HGNC:27310): (folliculin) This gene is located within the Smith-Magenis syndrome region on chromosome 17. Mutations in this gene are associated with Birt-Hogg-Dube syndrome, which is characterized by fibrofolliculomas, renal tumors, lung cysts, and pneumothorax. Alternative splicing of this gene results in two transcript variants encoding different isoforms. [provided by RefSeq, Jul 2008]
FLCN Gene-Disease associations (from GenCC):
  • Birt-Hogg-Dube syndrome
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Orphanet, ClinGen
  • Birt-Hogg-Dube syndrome 1
    Inheritance: AD Classification: DEFINITIVE Submitted by: G2P, Ambry Genetics
  • familial spontaneous pneumothorax
    Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet, Ambry Genetics
  • renal carcinoma
    Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
  • colorectal cancer
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -1 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 36 uncertain in NM_144997.7
PP3
MetaRNN computational evidence supports a deleterious effect, 0.785
BS2
High AC in GnomAdExome4 at 70 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FLCNNM_144997.7 linkc.535C>T p.Arg179Trp missense_variant Exon 6 of 14 ENST00000285071.9 NP_659434.2 Q8NFG4-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FLCNENST00000285071.9 linkc.535C>T p.Arg179Trp missense_variant Exon 6 of 14 1 NM_144997.7 ENSP00000285071.4 Q8NFG4-1
ENSG00000264187ENST00000427497.3 linkn.148+3985C>T intron_variant Intron 4 of 11 1 ENSP00000394249.3 J3QW42

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152166
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
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:
0.0000518
AC:
13
AN:
250976
AF XY:
0.0000368
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000882
Gnomad OTH exome
AF:
0.000326
GnomAD4 exome
AF:
0.0000479
AC:
70
AN:
1461380
Hom.:
1
Cov.:
32
AF XY:
0.0000495
AC XY:
36
AN XY:
726986
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.0000671
AC:
3
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86252
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52928
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000540
AC:
60
AN:
1112002
Other (OTH)
AF:
0.0000828
AC:
5
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.470
Heterozygous variant carriers
0
5
11
16
22
27
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:
0.0000131
AC:
2
AN:
152166
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74354
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41436
American (AMR)
AF:
0.0000654
AC:
1
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
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:
0.0000147
AC:
1
AN:
68016
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.550
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.0000712
Hom.:
0
Bravo
AF:
0.0000113
ExAC
AF:
0.0000576
AC:
7

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:7Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:2
Mar 01, 2024
CeGaT Center for Human Genetics Tuebingen
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

FLCN: PP3 -

Sep 26, 2023
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Observed in individual(s) with colorectal cancer (Bhai et al., 2021); This variant is associated with the following publications: (PMID: 34326862) -

Birt-Hogg-Dube syndrome 1 Uncertain:1Benign:1
Oct 23, 2024
Myriad Genetics, Inc.
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is considered likely benign. This variant has been observed at a population frequency that is significantly greater than expected given the associated disease prevalence and penetrance. -

Jun 17, 2025
St. Jude Molecular Pathology, St. Jude Children's Research Hospital
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The FLCN c.535C>T p.(Arg179Trp) missense change has a maximum subpopulation frequency of 0.0085% in gnomAD v2.1.1 (https://gnomad.broadinstitute.org). The in silico tool REVEL predicts a deleterious effect on protein function, but to our knowledge this prediction has not been confirmed by functional studies. To our knowledge, this variant has not been reported in individuals with Birt-Hogg-Dubai syndrome. In summary, the evidence currently available is insufficient to determine the clinical significance of this variant. It has therefore been classified as of uncertain significance. -

not specified Uncertain:1
Mar 04, 2025
Center for Genomic Medicine, Rigshospitalet, Copenhagen University Hospital
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

17p11.2 microduplication syndrome Uncertain:1
Oct 04, 2018
Centre for Mendelian Genomics, University Medical Centre Ljubljana
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was classified as: Uncertain significance. The available evidence on this variant's pathogenicity is insufficient or conflicting. The following ACMG criteria were applied in classifying this variant: PP3,BP1. -

Birt-Hogg-Dube syndrome;C0346629:Colorectal cancer;C1868193:Familial spontaneous pneumothorax;C2931246:17p11.2 microduplication syndrome;CN074294:Nonpapillary renal cell carcinoma Uncertain:1
May 11, 2022
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Birt-Hogg-Dube syndrome Uncertain:1
Feb 04, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 179 of the FLCN protein (p.Arg179Trp). This variant is present in population databases (rs774358971, gnomAD 0.008%), and has an allele count higher than expected for a pathogenic variant. This missense change has been observed in individual(s) with FLCN-related conditions (PMID: 34326862). ClinVar contains an entry for this variant (Variation ID: 409403). Invitae Evidence 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 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 FLCN protein function. 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. -

Hereditary cancer-predisposing syndrome Benign:1
Nov 15, 2022
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.97
BayesDel_addAF
Pathogenic
0.29
D
BayesDel_noAF
Pathogenic
0.36
CADD
Pathogenic
32
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.96
D;.;D
Eigen
Pathogenic
0.73
Eigen_PC
Pathogenic
0.73
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Uncertain
0.92
D;D;D
M_CAP
Pathogenic
0.33
D
MetaRNN
Pathogenic
0.79
D;D;D
MetaSVM
Uncertain
0.63
D
MutationAssessor
Uncertain
2.1
M;M;.
PhyloP100
4.2
PrimateAI
Pathogenic
0.84
D
PROVEAN
Pathogenic
-5.0
D;D;D
REVEL
Pathogenic
0.66
Sift
Uncertain
0.0010
D;D;D
Sift4G
Uncertain
0.0020
D;D;D
Polyphen
1.0
D;D;.
Vest4
0.88
MutPred
0.44
Loss of sheet (P = 0.0817);Loss of sheet (P = 0.0817);.;
MVP
0.87
MPC
1.2
ClinPred
0.60
D
GERP RS
5.7
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.89
gMVP
0.85
Mutation Taster
=52/48
polymorphism

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: rs774358971; hg19: chr17-17127319; COSMIC: COSV53259513; API