Genetic Variant FLCN:c.249+4A>G (chr17-17227885-T-C) – ACMG Classification: Likely_benign (-5 pts)

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 0P and 5B. BP6BS2

The NM_144997.7(FLCN):c.249+4A>G variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000397 in 1,613,956 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 0.000020 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000042 ( 0 hom. )

Consequence

FLCN
NM_144997.7 splice_region, intron

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:3

Conservation

PhyloP100: 2.59

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 links:

ENSG00000264187 (HGNC:):

ENSG00000264187 links:

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ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -5 ACMG points.

BP6

Variant 17-17227885-T-C is Benign according to our data. Variant chr17-17227885-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 485581.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=2, Uncertain_significance=3}.

BS2

High AC in GnomAdExome4 at 61 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FLCN	NM_144997.7 link	c.249+4A>G		splice_region_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
FLCN	ENST00000285071.9 link	c.249+4A>G		splice_region_variant, intron_variant	Intron 4 of 13	1	NM_144997.7	ENSP00000285071.4		Q8NFG4-1
ENSG00000264187	ENST00000427497.3 link	n.148+105A>G		intron_variant	Intron 4 of 11	1		ENSP00000394249.3		J3QW42

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152162

Hom.:

Cov.:

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:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000441

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000279

AC:

AN:

250732

Hom.:

AF XY:

0.0000295

AC XY:

AN XY:

135632

show subpopulations

Gnomad AFR exome

AF:

0.0000615

Gnomad AMR exome

AF:

0.0000289

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000544

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000354

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000417

AC:

AN:

1461794

Hom.:

Cov.:

AF XY:

0.0000509

AC XY:

AN XY:

727190

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.0000224

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:

0.0000531

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152162

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74342

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:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000441

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000565

Hom.:

Bravo

AF:

0.0000189

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:3Benign:3

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Uncertain:2

Aug 13, 2024

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In silico analysis supports a deleterious effect on splicing; Has not been previously published as pathogenic or benign to our knowledge -

Sep 19, 2024

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The FLCN c.249+4A>G variant has not been reported in individuals with FLCN-related conditions in the published literature. The frequency of this variant in the general population, 0.000035 (4/113030 chromosomes (Genome Aggregation Database, http://gnomad.broadinstitute.org)), is uninformative in the assessment of its pathogenicity. Analysis of this variant using software algorithms for the prediction of the effect of nucleotide changes on FLCN mRNA splicing yielded predictions that this variant may result in the gain of a cryptic splice site without affecting the natural splice sites. Based on the available information, we are unable to determine the clinical significance of this variant. -

Birt-Hogg-Dube syndrome

Uncertain:1Benign:1

Jul 25, 2022

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Feb 02, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Birt-Hogg-Dube syndrome 1

Benign:1

Oct 22, 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 is intronic and is not expected to impact mRNA splicing. This variant has been observed at a population frequency that is significantly greater than expected given the associated disease prevalence and penetrance. -

Hereditary cancer-predisposing syndrome

Benign:1

Jun 06, 2023

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

BayesDel_noAF

Benign

-0.26

CADD

Benign

DANN

Benign

0.96

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.26

Details are displayed if max score is > 0.2

DS_DG_spliceai

0.26

Position offset: 0

DS_DL_spliceai

0.21

Position offset: 4

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over