Genetic Variant FASN:c.4122+5G>A (chr17-82085477-C-T) – ACMG Classification: Benign (-8 pts)

Variant summary

Our verdict is Benign. Variant got -8 ACMG points: 0P and 8B. BP4_StrongBS2

The NM_004104.5(FASN):c.4122+5G>A variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000321 in 1,589,210 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

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

Exomes 𝑓: 0.000034 ( 0 hom. )

Consequence

FASN
NM_004104.5 splice_region, intron

Scores

Splicing: ADA: 0.3869

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -2.08

Variant links:

Genes affected

FASN (HGNC:3594): (fatty acid synthase) The enzyme encoded by this gene is a multifunctional protein. Its main function is to catalyze the synthesis of palmitate from acetyl-CoA and malonyl-CoA, in the presence of NADPH, into long-chain saturated fatty acids. In some cancer cell lines, this protein has been found to be fused with estrogen receptor-alpha (ER-alpha), in which the N-terminus of FAS is fused in-frame with the C-terminus of ER-alpha. [provided by RefSeq, Jul 2008]

FASN links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -8 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.87).

BS2

High AC in GnomAdExome4 at 49 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FASN	NM_004104.5 link	c.4122+5G>A		splice_region_variant, intron_variant	Intron 23 of 42	ENST00000306749.4	NP_004095.4	P49327
FASN	XM_011523538.3 link	c.4122+5G>A		splice_region_variant, intron_variant	Intron 23 of 42		XP_011521840.1	P49327

Ensembl

Gene	Transcript	HGVSc	Effect	Exon rank	TSL	MANE	Protein	UniProt
FASN	ENST00000306749.4 link	c.4122+5G>A	splice_region_variant, intron_variant	Intron 23 of 42	1	NM_004104.5	ENSP00000304592.2	P49327
FASN	ENST00000634990.1 link	c.4116+5G>A	splice_region_variant, intron_variant	Intron 23 of 42	5		ENSP00000488964.1	A0A0U1RQF0
FASN	ENST00000579410.1 link	n.179+5G>A	splice_region_variant, intron_variant	Intron 1 of 1	2

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152198

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:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000740

AC:

AN:

202742

Hom.:

AF XY:

0.0000902

AC XY:

AN XY:

110902

show subpopulations

Gnomad AFR exome

AF:

0.0000898

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.000159

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000341

AC:

AN:

1437012

Hom.:

Cov.:

AF XY:

0.0000351

AC XY:

AN XY:

712742

show subpopulations

Gnomad4 AFR exome

AF:

0.0000910

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000522

Gnomad4 SAS exome

AF:

0.0000120

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000336

Gnomad4 OTH exome

AF:

0.000101

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152198

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74338

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:

0.0000294

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000189

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Epileptic encephalopathy

Uncertain:1

Jun 19, 2021

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. Nucleotide substitutions within the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site, but this prediction has not been confirmed by published transcriptional studies. This variant has not been reported in the literature in individuals with FASN-related disease. This variant is present in population databases (rs750312479, ExAC 0.03%), and has an allele count higher than expected for a pathogenic variant (PMID: 28166811). This sequence change falls in intron 23 of the FASN gene. It does not directly change the encoded amino acid sequence of the FASN protein, but it affects a nucleotide within the consensus splice site of the intron. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.87

CADD

Benign

1.2

DANN

Benign

0.71

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Benign

0.39

dbscSNV1_RF

Benign

0.28

SpliceAI score (max)

0.040

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

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