6-129353285-C-G

Variant names:

• chr6-129353285-C-G
• rs121913575
• NM_000426.4:c.4645C>G

Variant summary

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

The NM_000426.4(LAMA2):​c.4645C>G​(p.Arg1549Gly) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,826 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R1549Q) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: LAMA2 NM_000426.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 4.45
• Publications: 0 publications found

Genes affected

LAMA2 (HGNC:6482): (laminin subunit alpha 2) Laminin, an extracellular protein, is a major component of the basement membrane. It is thought to mediate the attachment, migration, and organization of cells into tissues during embryonic development by interacting with other extracellular matrix components. It is composed of three subunits, alpha, beta, and gamma, which are bound to each other by disulfide bonds into a cross-shaped molecule. This gene encodes the alpha 2 chain, which constitutes one of the subunits of laminin 2 (merosin) and laminin 4 (s-merosin). Mutations in this gene have been identified as the cause of congenital merosin-deficient muscular dystrophy. Two transcript variants encoding different proteins have been found for this gene. [provided by RefSeq, Jul 2008]

LAMA2 Gene-Disease associations (from GenCC):

• congenital merosin-deficient muscular dystrophy 1A

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), Myriad Women’s Health, G2P
• LAMA2-related muscular dystrophy

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• muscular dystrophy, limb-girdle, autosomal recessive 23

  Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
LAMA2	NM_000426.4	c.4645C>G	p.Arg1549Gly	missense_variant	Exon 32 of 65	ENST00000421865.3	NP_000417.3
LAMA2	NM_001079823.2	c.4645C>G	p.Arg1549Gly	missense_variant	Exon 32 of 64		NP_001073291.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
LAMA2	ENST00000421865.3	c.4645C>G	p.Arg1549Gly	missense_variant	Exon 32 of 65	5	NM_000426.4	ENSP00000400365.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461826 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727212

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39696

South Asian (SAS) AF: 0.00 AC: 0 AN: 86246

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

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

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111966

Other (OTH) AF: 0.0000166 AC: 1 AN: 60390

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.19
BayesDel_addAF	Uncertain	0.048	T
BayesDel_noAF	Benign	-0.17
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Benign	0.070	.;T;T
Eigen	Uncertain	0.52
Eigen_PC	Uncertain	0.47
FATHMM_MKL	Uncertain	0.78	D
LIST_S2	Benign	0.82	T;T;T
M_CAP	Uncertain	0.15	D
MetaRNN	Uncertain	0.54	D;D;D
MetaSVM	Benign	-0.46	T
MutationAssessor	Pathogenic	3.4	.;.;M
PhyloP100		4.5
PrimateAI	Benign	0.42	T
PROVEAN	Pathogenic	-4.6	.;.;D
REVEL	Uncertain	0.36
Sift	Uncertain	0.0040	.;.;D
Polyphen		0.90	.;.;P
Vest4		0.36
MutPred		0.64		Gain of glycosylation at T1547 (P = 0.1227);Gain of glycosylation at T1547 (P = 0.1227);Gain of glycosylation at T1547 (P = 0.1227);
MVP		0.86
MPC		0.48
ClinPred		0.96	D
GERP RS		3.9
Varity_R		0.75
gMVP		0.82
Mutation Taster		=75/25	polymorphism

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: rs121913575; hg19: chr6-129674430;