rs1555611550

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 1P and 1B. PP3BS2_Supporting

The NM_144997.7(FLCN):​c.59T>A​(p.Phe20Tyr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000479 in 1,461,294 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 Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. F20F) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

FLCN
NM_144997.7 missense

Scores

9
5
4

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 8.63

Publications

0 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: Uncertain_significance. The variant received 0 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.804
BS2
High AC in GnomAdExome4 at 7 AD gene. Variant has AC lower than other variant known as pathogenic in the gene, so the strength is limited to Supporting.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FLCNNM_144997.7 linkc.59T>A p.Phe20Tyr missense_variant Exon 4 of 14 ENST00000285071.9 NP_659434.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FLCNENST00000285071.9 linkc.59T>A p.Phe20Tyr missense_variant Exon 4 of 14 1 NM_144997.7 ENSP00000285071.4
ENSG00000264187ENST00000427497.3 linkn.59T>A non_coding_transcript_exon_variant Exon 4 of 12 1 ENSP00000394249.3

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD4 exome
AF:
0.00000479
AC:
7
AN:
1461294
Hom.:
0
Cov.:
31
AF XY:
0.00000413
AC XY:
3
AN XY:
726954
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52828
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000540
AC:
6
AN:
1112012
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.511
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

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
Cov.:
33

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1
Mar 26, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.F20Y variant (also known as c.59T>A), located in coding exon 1 of the FLCN gene, results from a T to A substitution at nucleotide position 59. The phenylalanine at codon 20 is replaced by tyrosine, an amino acid with highly similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear.

Birt-Hogg-Dube syndrome Uncertain:1
Dec 29, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces phenylalanine, which is neutral and non-polar, with tyrosine, which is neutral and polar, at codon 20 of the FLCN protein (p.Phe20Tyr). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with FLCN-related conditions. ClinVar contains an entry for this variant (Variation ID: 460621). 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) indicates that this missense variant is not expected to disrupt FLCN protein function with a negative predictive value of 80%. 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.

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.75
BayesDel_addAF
Pathogenic
0.43
D
BayesDel_noAF
Pathogenic
0.38
CADD
Uncertain
25
DANN
Benign
0.94
DEOGEN2
Benign
0.39
T;.;.
Eigen
Uncertain
0.68
Eigen_PC
Pathogenic
0.70
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Benign
0.77
T;T;T
M_CAP
Uncertain
0.28
D
MetaRNN
Pathogenic
0.80
D;D;D
MetaSVM
Pathogenic
0.89
D
MutationAssessor
Uncertain
2.3
M;M;.
PhyloP100
8.6
PrimateAI
Pathogenic
0.88
D
PROVEAN
Benign
-2.1
N;N;.
REVEL
Pathogenic
0.86
Sift
Uncertain
0.011
D;D;.
Sift4G
Uncertain
0.032
D;D;.
Vest4
0.87
ClinPred
0.93
D
GERP RS
5.5
Varity_R
0.57
gMVP
0.81
Mutation Taster
=47/53
disease causing

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: rs1555611550; hg19: chr17-17131393; API