chr17-17216382-G-A

Position:

• chr17-17216382-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_144997.7(FLCN):​c.1298C>T​(p.Ser433Leu) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,170 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: FLCN NM_144997.7 missense, splice_region
• Scores: Splicing: ADA: 0.9985
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 9.15

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]

ENSG00000264187 (HGNC:):

MPRIP (HGNC:30321): (myosin phosphatase Rho interacting protein) Enables cadherin binding activity. Predicted to be involved in actin filament organization. Located in actin cytoskeleton and cytosol. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.9

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
FLCN	NM_144997.7	c.1298C>T	p.Ser433Leu	missense_variant, splice_region_variant	11/14	ENST00000285071.9	NP_659434.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
FLCN	ENST00000285071.9	c.1298C>T	p.Ser433Leu	missense_variant, splice_region_variant	11/14	1	NM_144997.7	ENSP00000285071.4
ENSG00000264187	ENST00000427497.3	n.*132C>T		splice_region_variant, non_coding_transcript_exon_variant	7/12	1		ENSP00000394249.3
ENSG00000264187	ENST00000427497.3	n.*132C>T		3_prime_UTR_variant	7/12	1		ENSP00000394249.3
MPRIP	ENST00000578209.5	c.*18-1108G>A		intron_variant		3		ENSP00000464276.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461170 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 726894

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

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: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 09, 2024

The p.S433L variant (also known as c.1298C>T), located in coding exon 8 of the FLCN gene, results from a C to T substitution at nucleotide position 1298. The serine at codon 433 is replaced by leucine, an amino acid with dissimilar 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. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Birt-Hogg-Dube syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 25, 2023

This sequence change replaces serine, which is neutral and polar, with leucine, which is neutral and non-polar, at codon 433 of the FLCN protein (p.Ser433Leu). 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: 409397). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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	Uncertain	0.41
BayesDel_addAF	Pathogenic	0.47	D
BayesDel_noAF	Pathogenic	0.43
CADD	Pathogenic	34
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.77	D
Eigen	Pathogenic	0.82
Eigen_PC	Pathogenic	0.83
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.95	D
M_CAP	Pathogenic	0.50	D
MetaRNN	Pathogenic	0.90	D
MetaSVM	Pathogenic	0.80	D
MutationAssessor	Uncertain	2.1	M
PrimateAI	Uncertain	0.66	T
PROVEAN	Uncertain	-2.5	D
REVEL	Pathogenic	0.71
Sift	Benign	0.047	D
Sift4G	Uncertain	0.029	D
Polyphen		1.0	D
Vest4		0.95
MutPred		0.45		Gain of sheet (P = 0.0477);
MVP		0.69
MPC		0.94
ClinPred		0.94	D
GERP RS		5.7
Varity_R		0.49
gMVP		0.76

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.84
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs1060502372; hg19: chr17-17119696;