chr6-129098371-T-A

Variant names:

• chr6-129098371-T-A
• rs886043693
• NM_000426.4:c.595T>A

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_000426.4(LAMA2):​c.595T>A​(p.Cys199Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000547 in 1,461,778 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. C199C) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000055 (0 hom.)
• Consequence: LAMA2 NM_000426.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:5
• Conservation: PhyloP100: 8.01
• Publications: 1 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: Labcorp Genetics (formerly Invitae), Orphanet, G2P, Myriad Women’s Health
• 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: Likely_pathogenic. The variant received 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.985

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000426.4. 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
	LAMA2	NM_000426.4	MANE Select	c.595T>A	p.Cys199Ser	missense	Exon 4 of 65	NP_000417.3
	LAMA2	NM_001079823.2		c.595T>A	p.Cys199Ser	missense	Exon 4 of 64	NP_001073291.2	A0A087WYF1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	LAMA2	ENST00000421865.3	TSL:5 MANE Select	c.595T>A	p.Cys199Ser	missense	Exon 4 of 65	ENSP00000400365.2	P24043
	LAMA2	ENST00000618192.5	TSL:5	c.595T>A	p.Cys199Ser	missense	Exon 4 of 66	ENSP00000480802.2	A0A087WX80
	LAMA2	ENST00000617695.5	TSL:5	c.595T>A	p.Cys199Ser	missense	Exon 4 of 64	ENSP00000481744.2	A0A087WYF1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251416 AF XY: 0.00000736

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000547 AC: 8 AN: 1461778 Hom.: 0 Cov.: 32 AF XY: 0.00000550 AC XY: 4 AN XY: 727202

African (AFR) AF: 0.00 AC: 0 AN: 33476

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

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26130

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

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

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: 0.00000630 AC: 7 AN: 1111914

Other (OTH) AF: 0.0000166 AC: 1 AN: 60392

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	1	-	Congenital muscular dystrophy due to partial LAMA2 deficiency (1)
-	1	-	LAMA2-related muscular dystrophy (1)
-	1	-	Merosin deficient congenital muscular dystrophy (1)
-	1	-	not provided (1)
-	1	-	not specified (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.46	D
BayesDel_noAF	Pathogenic	0.42
CADD	Pathogenic	28
DANN	Uncertain	0.99
DEOGEN2	Benign	0.079	T
Eigen	Pathogenic	0.96
Eigen_PC	Pathogenic	0.87
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.89	D
M_CAP	Uncertain	0.23	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	0.94	D
MutationAssessor	Pathogenic	4.3	H
PhyloP100		8.0
PrimateAI	Pathogenic	0.88	D
PROVEAN	Pathogenic	-9.4	D
REVEL	Pathogenic	0.97
Sift	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.97
MutPred		0.94		Gain of disorder (P = 0.0018)
MVP		0.92
MPC		0.53
ClinPred		1.0	D
GERP RS		5.3
Varity_R		0.98
gMVP		0.95
Mutation Taster		=34/66	disease causing

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: rs886043693; hg19: chr6-129419516;