5-139318946-C-A

Variant names:

• chr5-139318946-C-A
• rs141986556
• NM_018834.6:c.1347C>A

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2 BP4 BP7

The NM_018834.6(MATR3):​c.1347C>A​(p.Ala449Ala) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,758 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. A449A) has been classified as Benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MATR3 NM_018834.6 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.426
• Publications: 0 publications found

Genes affected

MATR3 (HGNC:6912): (matrin 3) This gene encodes a nuclear matrix protein, which is proposed to stabilize certain messenger RNA species. Mutations of this gene are associated with distal myopathy 2, which often includes vocal cord and pharyngeal weakness. Alternatively spliced transcript variants, including read-through transcripts composed of the upstream small nucleolar RNA host gene 4 (non-protein coding) and matrin 3 gene sequence, have been identified. Pseudogenes of this gene are located on chromosomes 1 and X. [provided by RefSeq, Aug 2013]

MATR3 Gene-Disease associations (from GenCC):

• distal myopathy with vocal cord weakness

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen
• amyotrophic lateral sclerosis type 21

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Ambry Genetics
• amyotrophic lateral sclerosis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (REVEL=0.265).
• BP7: Synonymous conserved (PhyloP=0.426 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_018834.6. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MATR3	NM_018834.6	MANE Select	c.1347C>A	p.Ala449Ala	synonymous	Exon 8 of 15	NP_061322.2
	MATR3	NM_001400441.1		c.1347C>A	p.Ala449Ala	synonymous	Exon 9 of 16	NP_001387370.1	A8MXP9
	MATR3	NM_001400442.1		c.1347C>A	p.Ala449Ala	synonymous	Exon 11 of 18	NP_001387371.1	A8MXP9

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MATR3	ENST00000394805.8	TSL:1 MANE Select	c.1347C>A	p.Ala449Ala	synonymous	Exon 8 of 15	ENSP00000378284.3	P43243-1
	MATR3	ENST00000502929.5	TSL:2	c.1347C>A	p.Ala449Ala	synonymous	Exon 13 of 20	ENSP00000422319.1	A8MXP9
	MATR3	ENST00000618441.5	TSL:1	c.1347C>A	p.Ala449Ala	synonymous	Exon 8 of 15	ENSP00000482895.1	P43243-1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461758 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727198

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53418

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111892

Other (OTH) AF: 0.00 AC: 0 AN: 60392

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.23
CADD	Benign	8.3
DANN	Benign	0.56
PhyloP100		0.43
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

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: rs141986556; hg19: chr5-138654635;