rs939223011

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 4P and 1B. PVS1_StrongBP6

The NM_144997.7(FLCN):​c.249+2C>T variant causes a splice donor, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000372 in 1,613,986 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 1/1 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

FLCN
NM_144997.7 splice_donor, intron

Scores

1
3
3

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4B:2

Conservation

PhyloP100: 0.614

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 3 ACMG points.

PVS1
Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.15689655 fraction of the gene. Cryptic splice site detected, with MaxEntScore 11, offset of 0 (no position change), new splice context is: gagGTaagt. Cryptic site results in inframe change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
BP6
Variant 17-17227887-G-A is Benign according to our data. Variant chr17-17227887-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 409382.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FLCNNM_144997.7 linkc.249+2C>T splice_donor_variant, intron_variant Intron 4 of 13 ENST00000285071.9 NP_659434.2 Q8NFG4-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FLCNENST00000285071.9 linkc.249+2C>T splice_donor_variant, intron_variant Intron 4 of 13 1 NM_144997.7 ENSP00000285071.4 Q8NFG4-1
ENSG00000264187ENST00000427497.3 linkn.148+103C>T intron_variant Intron 4 of 11 1 ENSP00000394249.3 J3QW42

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152192
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000196
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
GnomAD4 exome
AF:
0.00000205
AC:
3
AN:
1461794
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
727188
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.0000224
AC:
1
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:
53352
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1111998
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60388
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.492
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.0000197
AC:
3
AN:
152192
Hom.:
0
Cov.:
33
AF XY:
0.0000404
AC XY:
3
AN XY:
74348
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41450
American (AMR)
AF:
0.000196
AC:
3
AN:
15280
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:
10612
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68032
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.675
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:4Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:2
Jul 21, 2023
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Affects a canonical splice site; however, in silico analysis supports that this variant does not alter splicing; Not observed at significant frequency in large population cohorts (gnomAD); Has not been previously published as pathogenic or benign to our knowledge -

Mar 17, 2023
Quest Diagnostics Nichols Institute San Juan Capistrano
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant disrupts a canonical splice-donor site and is predicted to interfere with normal FLCN mRNA splicing. The variant has not been reported in the published literature. The frequency of this variant in the general population, 0.00022 (3/13742 chromosomes in Latino/Admixed American subpopulation, http://gnomad.broadinstitute.org), is higher than would generally be expected for pathogenic variants in this gene. Based on the available information, we are unable to determine the clinical significance of this variant. -

Birt-Hogg-Dube syndrome;C0346629:Colorectal cancer;C1868193:Familial spontaneous pneumothorax;C2931246:17p11.2 microduplication syndrome;CN074294:Nonpapillary renal cell carcinoma Uncertain:1
Oct 07, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Hereditary cancer-predisposing syndrome Uncertain:1
Jul 16, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.249+2C>T intronic variant results from a C to T substitution two nucleotides after coding exon 1 in the FLCN gene. This nucleotide position is not well conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will not have any significant effect on splicing; however, direct evidence is insufficient at this time (Ambry internal data). Based on the available evidence, the clinical significance of this variant remains unclear. -

Birt-Hogg-Dube syndrome 1 Benign:1
Dec 19, 2023
Myriad Genetics, Inc.
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is considered likely benign. Although this variant occurs at the canonical splice site, it changes the splice site to consensus and is not expected to impact RNA splicing. -

Birt-Hogg-Dube syndrome Benign:1
Dec 26, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.63
D
BayesDel_noAF
Uncertain
-0.030
CADD
Benign
20
DANN
Benign
0.88
Eigen
Uncertain
0.68
Eigen_PC
Uncertain
0.46
FATHMM_MKL
Benign
0.50
D
PhyloP100
0.61
GERP RS
0.99

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.080
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: rs939223011; hg19: chr17-17131201; COSMIC: COSV99550611; COSMIC: COSV99550611; API