NM_170707.4:c.1608+5G>C

Variant names:

• chr1-156137237-G-C
• rs267607539
• NM_170707.4:c.1608+5G>C

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP5_Moderate

The NM_170707.4(LMNA):​c.1608+5G>C variant causes a splice region, intron change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: LMNA NM_170707.4 splice_region, intron
• Scores: Splicing: ADA: 0.9989
• Clinical Significance: Pathogenic criteria provided, single submitter P:4 O:1
• Conservation: PhyloP100: 6.34

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 1-156137237-G-C is Pathogenic according to our data. Variant chr1-156137237-G-C is described in ClinVar as [Pathogenic]. Clinvar id is 66854.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-156137237-G-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
LMNA	NM_170707.4	c.1608+5G>C		splice_region_variant, intron_variant	Intron 9 of 11	ENST00000368300.9	NP_733821.1
LMNA	NM_005572.4	c.1608+5G>C		splice_region_variant, intron_variant	Intron 9 of 9	ENST00000677389.1	NP_005563.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
LMNA	ENST00000368300.9	c.1608+5G>C		splice_region_variant, intron_variant	Intron 9 of 11	1	NM_170707.4	ENSP00000357283.4
LMNA	ENST00000677389.1	c.1608+5G>C		splice_region_variant, intron_variant	Intron 9 of 9		NM_005572.4	ENSP00000503633.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:4 Other:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Pathogenic:2 Other:1

-

Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

-

Epithelial Biology; Institute of Medical Biology, Singapore

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

- -

-

Genome Diagnostics Laboratory, University Medical Center Utrecht

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Cardiovascular phenotype Pathogenic:1

Sep 14, 2017

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.1608+5G>C intronic pathogenic mutation results from a G to C substitution 5 nucleotides after coding exon 9 in the LMNA gene. This mutation strongly segregated with disease in two families with limb-girdle muscular dystrophy (LGMD1B) or LMNA-related dilated cardiomyopathy (Muchir A et al. Hum. Mol. Genet. 2000;9:1453-9; Hoedemaekers YM et al. Circ Cardiovasc Genet, 2010 Jun;3:232-9). RNA studies indicate that this alteration impacts splicing, causing retention of intron 9 and leading to a frameshift and premature truncation of the LMNA protein (Muchir A et al. Hum. Mol. Genet. 2000;9:1453-9). Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -

Emery-Dreifuss muscular dystrophy 2, autosomal dominant Pathogenic:1

May 22, 2000

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.50
CADD	Benign	19
DANN	Benign	0.80
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.0

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.68		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.68		Position offset: -34
DS_DL_spliceai		0.46		Position offset: -5

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

Publications

LitVar

Other links and lift over

dbSNP: rs267607539; hg19: chr1-156107028;