rs1556639379

Variant names:

• chrX-136208564-A-AG
• rs1556639379
• NM_001159702.3:c.613dupG

Variant summary

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

The NM_001159702.3(FHL1):​c.613dupG​(p.Asp205GlyfsTer39) variant causes a frameshift change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 22)
• Consequence: FHL1 NM_001159702.3 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 5.67
• Publications: 0 publications found

Genes affected

FHL1 (HGNC:3702): (four and a half LIM domains 1) This gene encodes a member of the four-and-a-half-LIM-only protein family. Family members contain two highly conserved, tandemly arranged, zinc finger domains with four highly conserved cysteines binding a zinc atom in each zinc finger. Expression of these family members occurs in a cell- and tissue-specific mode and these proteins are involved in many cellular processes. Mutations in this gene have been found in patients with Emery-Dreifuss muscular dystrophy. Multiple alternately spliced transcript variants which encode different protein isoforms have been described.[provided by RefSeq, Nov 2009]

FHL1 Gene-Disease associations (from GenCC):

• X-linked myopathy with postural muscle atrophy

  Inheritance: XL Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, G2P
• myopathy, reducing body, X-linked, early-onset, severe

  Inheritance: XL Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• reducing body myopathy

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet
• X-linked Emery-Dreifuss muscular dystrophy

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet
• X-linked scapuloperoneal muscular dystrophy

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

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

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant X-136208564-A-AG is Pathogenic according to our data. Variant chrX-136208564-A-AG is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 537351.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
FHL1	NM_001159702.3	c.613dupG	p.Asp205GlyfsTer39	frameshift_variant	Exon 6 of 8	ENST00000394155.8	NP_001153174.1
FHL1	NM_001159699.2	c.661dupG	p.Asp221GlyfsTer29	frameshift_variant	Exon 5 of 6	ENST00000370683.6	NP_001153171.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FHL1	ENST00000394155.8	c.613dupG	p.Asp205GlyfsTer39	frameshift_variant	Exon 6 of 8	5	NM_001159702.3	ENSP00000377710.2
FHL1	ENST00000370683.6	c.661dupG	p.Asp221GlyfsTer29	frameshift_variant	Exon 5 of 6	1	NM_001159699.2	ENSP00000359717.1

Frequencies

GnomAD3 genomes Cov.: 22

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 22

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

X-linked myopathy with postural muscle atrophy Pathogenic:1

Feb 01, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Asp205Glyfs*29) in the FHL1 gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 76 amino acid(s) of the FHL1 protein. This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with FHL1-related conditions. ClinVar contains an entry for this variant (Variation ID: 537351). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. This variant disrupts a region of the FHL1 protein in which other variant(s) (p.Cys209Thrfs*50) have been determined to be pathogenic (PMID: 25246303, 26857240; Invitae). This suggests that this is a clinically significant region of the protein, and that variants that disrupt it are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

not provided Pathogenic:1

May 14, 2021

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Has not been previously published as pathogenic or benign to our knowledge; Not observed in large population cohorts (Lek et al., 2016); Frameshift variant predicted to result in protein truncation, as the last 76 amino acids are replaced with 28 different amino acids, and other loss-of-function variants have been reported downstream in the Human Gene Mutation Database (Stenson et al., 2014) -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		5.7
Mutation Taster		=0/200	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs1556639379; hg19: chrX-135290723;