NM_007078.3:c.1074C>A

Variant names:

• chr10-86706708-C-A
• rs45459491
• NM_007078.3:c.1074C>A

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_007078.3(LDB3):​c.1074C>A​(p.Ala358Ala) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. A358A) has been classified as Benign.

• Frequency: Genomes: not found (cov: 33)
• Consequence: LDB3 NM_007078.3 synonymous
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.0710
• Publications: 0 publications found

Genes affected

LDB3 (HGNC:15710): (LIM domain binding 3) This gene encodes a PDZ domain-containing protein. PDZ motifs are modular protein-protein interaction domains consisting of 80-120 amino acid residues. PDZ domain-containing proteins interact with each other in cytoskeletal assembly or with other proteins involved in targeting and clustering of membrane proteins. The protein encoded by this gene interacts with alpha-actinin-2 through its N-terminal PDZ domain and with protein kinase C via its C-terminal LIM domains. The LIM domain is a cysteine-rich motif defined by 50-60 amino acids containing two zinc-binding modules. This protein also interacts with all three members of the myozenin family. Mutations in this gene have been associated with myofibrillar myopathy and dilated cardiomyopathy. Alternatively spliced transcript variants encoding different isoforms have been identified; all isoforms have N-terminal PDZ domains while only longer isoforms (1, 2 and 5) have C-terminal LIM domains. [provided by RefSeq, Jan 2010]

LDB3 Gene-Disease associations (from GenCC):

• myofibrillar myopathy 4

  Inheritance: AD Classification: STRONG, MODERATE, LIMITED Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
• familial isolated dilated cardiomyopathy

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

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen
• familial dilated cardiomyopathy

  Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics
• arrhythmogenic right ventricular cardiomyopathy

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.82).
• BP7: Synonymous conserved (PhyloP=0.071 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
LDB3	NM_007078.3	c.1074C>A	p.Ala358Ala	synonymous_variant	Exon 8 of 14	ENST00000361373.9	NP_009009.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
LDB3	ENST00000361373.9	c.1074C>A	p.Ala358Ala	synonymous_variant	Exon 8 of 14	1	NM_007078.3	ENSP00000355296.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Myofibrillar myopathy 4 Uncertain:1

May 17, 2021

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects codon 358 of the LDB3 mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the LDB3 protein. The LDB3 gene has multiple clinically relevant transcripts. This variant occurs in alternate transcript NM_007078.3, and corresponds to NM_001080116.1:c.*7334C>A in the primary transcript. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with LDB3-related conditions. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site, but this prediction has not been confirmed by published transcriptional studies. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.82
CADD	Benign	0.92
DANN	Benign	0.46
PhyloP100		0.071

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs45459491; hg19: chr10-88466465;