rs1553265369

Variant names:

• chr1-156134953-TGGA-T
• rs1553265369
• NM_170707.4:c.790_792delGAG

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1 PM2 PM4_Supporting PP5

The NM_170707.4(LMNA):​c.790_792delGAG​(p.Glu264del) variant causes a conservative inframe deletion change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: LMNA NM_170707.4 conservative_inframe_deletion
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:1
• Conservation: PhyloP100: 9.92
• Publications: 0 publications found

Genes affected

LMNA (HGNC:6636): (lamin A/C) The protein encoded by this gene is part of the nuclear lamina, a two-dimensional matrix of proteins located next to the inner nuclear membrane. The lamin family of proteins make up the matrix and are highly conserved in evolution. During mitosis, the lamina matrix is reversibly disassembled as the lamin proteins are phosphorylated. Lamin proteins are thought to be involved in nuclear stability, chromatin structure and gene expression. Vertebrate lamins consist of two types, A and B. Alternative splicing results in multiple transcript variants. Mutations in this gene lead to several diseases: Emery-Dreifuss muscular dystrophy, familial partial lipodystrophy, limb girdle muscular dystrophy, dilated cardiomyopathy, Charcot-Marie-Tooth disease, and Hutchinson-Gilford progeria syndrome. [provided by RefSeq, May 2022]

LMNA Gene-Disease associations (from GenCC):

• dilated cardiomyopathy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• dilated cardiomyopathy 1A

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: G2P, Ambry Genetics, Orphanet
• familial partial lipodystrophy, Dunnigan type

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp, G2P, Labcorp Genetics (formerly Invitae)
• Hutchinson-Gilford progeria syndrome

  Inheritance: AD, SD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Orphanet, G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• restrictive dermopathy 2

  Inheritance: AR, AD Classification: DEFINITIVE, LIMITED Submitted by: G2P
• Emery-Dreifuss muscular dystrophy 2, autosomal dominant

  Inheritance: SD, AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P
• atrioventricular block

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
• heart-hand syndrome, Slovenian type

  Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, Ambry Genetics, G2P
• Charcot-Marie-Tooth disease type 2B1

  Inheritance: AR, AD Classification: STRONG, MODERATE, SUPPORTIVE, LIMITED Submitted by: G2P, Ambry Genetics, Orphanet, Labcorp Genetics (formerly Invitae)
• Emery-Dreifuss muscular dystrophy 3, autosomal recessive

  Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• mandibuloacral dysplasia with type A lipodystrophy

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet
• atrial fibrillation

  Inheritance: AD Classification: MODERATE Submitted by: Ambry Genetics
• atypical Werner syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• autosomal dominant Emery-Dreifuss muscular dystrophy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• congenital muscular dystrophy due to LMNA mutation

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial isolated dilated cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• lethal restrictive dermopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• LMNA-related cardiocutaneous progeria syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• autosomal recessive Emery-Dreifuss muscular dystrophy

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• dilated cardiomyopathy-hypergonadotropic hypogonadism syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• autosomal semi-dominant severe lipodystrophic laminopathy

  Inheritance: SD Classification: SUPPORTIVE Submitted by: Orphanet
• arrhythmogenic right ventricular cardiomyopathy

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM1: In a hotspot region, there are 7 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 22 uncertain in NM_170707.4
• PM2: Very rare variant in population databases, with high coverage
• PM4: Nonframeshift variant in NON repetitive region in NM_170707.4. Strenght limited to Supporting due to length of the change: 1aa.
• PP5: Variant 1-156134953-TGGA-T is Pathogenic according to our data. Variant chr1-156134953-TGGA-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 435776.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
LMNA	NM_170707.4	c.790_792delGAG	p.Glu264del	conservative_inframe_deletion	Exon 4 of 12	ENST00000368300.9	NP_733821.1
LMNA	NM_005572.4	c.790_792delGAG	p.Glu264del	conservative_inframe_deletion	Exon 4 of 10	ENST00000677389.1	NP_005563.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
LMNA	ENST00000368300.9	c.790_792delGAG	p.Glu264del	conservative_inframe_deletion	Exon 4 of 12	1	NM_170707.4	ENSP00000357283.4
LMNA	ENST00000677389.1	c.790_792delGAG	p.Glu264del	conservative_inframe_deletion	Exon 4 of 10		NM_005572.4	ENSP00000503633.1

Frequencies

GnomAD3 genomes Cov.: 32

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Muscular dystrophy Pathogenic:1

Feb 08, 2013

Genetic Services Laboratory, University of Chicago

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Charcot-Marie-Tooth disease type 2 Uncertain:1

Oct 17, 2022

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. Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. ClinVar contains an entry for this variant (Variation ID: 435776). This variant has not been reported in the literature in individuals affected with LMNA-related conditions. This variant is not present in population databases (gnomAD no frequency). This variant, c.790_792del, results in the deletion of 1 amino acid(s) of the LMNA protein (p.Glu264del), but otherwise preserves the integrity of the reading frame. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		9.9
Mutation Taster		=1/99	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.070		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: rs1553265369; hg19: chr1-156104744;