chrX-154366731-C-T

Variant names:

• chrX-154366731-C-T
• rs786205204
• NM_001110556.2:c.987+1G>A

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_001110556.2(FLNA):​c.987+1G>A variant causes a splice donor, intron change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency: Genomes: not found (cov: 24)
• Consequence: FLNA NM_001110556.2 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Likely pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 7.81
• Publications: 0 publications found

Genes affected

FLNA (HGNC:3754): (filamin A) The protein encoded by this gene is an actin-binding protein that crosslinks actin filaments and links actin filaments to membrane glycoproteins. The encoded protein is involved in remodeling the cytoskeleton to effect changes in cell shape and migration. This protein interacts with integrins, transmembrane receptor complexes, and second messengers. Defects in this gene are a cause of several syndromes, including periventricular nodular heterotopias (PVNH1, PVNH4), otopalatodigital syndromes (OPD1, OPD2), frontometaphyseal dysplasia (FMD), Melnick-Needles syndrome (MNS), and X-linked congenital idiopathic intestinal pseudoobstruction (CIIPX). Two transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Mar 2009]

FLNA Gene-Disease associations (from GenCC):

• periventricular nodular heterotopia

  Inheritance: AD, XL Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen
• frontometaphyseal dysplasia 1

  Inheritance: XL Classification: DEFINITIVE Submitted by: G2P
• genetic developmental and epileptic encephalopathy

  Inheritance: XL Classification: DEFINITIVE Submitted by: G2P
• heterotopia, periventricular, X-linked dominant

  Inheritance: XL Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae), Illumina
• intestinal pseudoobstruction, neuronal, chronic idiopathic, X-linked

  Inheritance: XL Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• Melnick-Needles syndrome

  Inheritance: XL Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Orphanet, Labcorp Genetics (formerly Invitae)
• otopalatodigital syndrome type 2

  Inheritance: XL Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet, G2P, Labcorp Genetics (formerly Invitae)
• terminal osseous dysplasia-pigmentary defects syndrome

  Inheritance: XL Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Orphanet, Labcorp Genetics (formerly Invitae)
• cardiac valvular dysplasia, X-linked

  Inheritance: XL Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Orphanet, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• frontometaphyseal dysplasia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• congenital short bowel syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• otopalatodigital syndrome type 1

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet
• X-linked Ehlers-Danlos syndrome

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet
• familial thoracic aortic aneurysm and aortic dissection

  Inheritance: XL Classification: LIMITED Submitted by: ClinGen

ACMG classification

Our verdict: Pathogenic. The variant received 18 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 4.4, offset of -34, new splice context is: ggtGTacgt. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant X-154366731-C-T is Pathogenic according to our data. Variant chrX-154366731-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 190205.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FLNA	NM_001110556.2	c.987+1G>A		splice_donor_variant, intron_variant	Intron 6 of 47	ENST00000369850.10	NP_001104026.1
FLNA	NM_001456.4	c.987+1G>A		splice_donor_variant, intron_variant	Intron 6 of 46		NP_001447.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FLNA	ENST00000369850.10	c.987+1G>A		splice_donor_variant, intron_variant	Intron 6 of 47	1	NM_001110556.2	ENSP00000358866.3

Frequencies

GnomAD3 genomes Cov.: 24

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 24

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

FLNA-related disorder Pathogenic:1

-

Rady Children's Institute for Genomic Medicine, Rady Children's Hospital San Diego

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant affects the canonical splice donor site of intron 6 and is therefore predicted to interfere with splicing and result in loss of normal protein function through either protein truncation or nonsense-mediated mRNA decay (NMD). This variant has not been previously reported or functionally characterized in the literature to our knowledge. A different nucleotide change (c.987G>C) affecting the same donor-splicing site has been described in a mother and daughter with bilateral periventricular nodular heterotopia (PMID: 18427995). It is absent from the gnomAD population database and thus is presumed to be rare. Based on the available evidence, the c.987+1G>A variant is classified as Likely Pathogenic. -

Heterotopia, periventricular, X-linked dominant Pathogenic:1

Jul 12, 2013

Claritas Genomics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.74	D
BayesDel_noAF	Pathogenic	0.32
CADD	Pathogenic	34
DANN	Uncertain	1.0
FATHMM_MKL	Uncertain	0.96	D
PhyloP100		7.8
GERP RS		5.2
PromoterAI		0.034	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		3.2
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.95
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.44		Position offset: 35
DS_DL_spliceai		0.99		Position offset: 1

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

Other links and lift over

dbSNP: rs786205204; hg19: chrX-153595099;