chr6-129473205-C-T

Variant names:

• chr6-129473205-C-T
• rs747783456
• NM_000426.4:c.7301-9C>T

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 2P and 6B. PM2 BP4_Strong BP6_Moderate

The NM_000426.4(LAMA2):​c.7301-9C>T variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000254 in 1,577,896 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★).

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: LAMA2 NM_000426.4 intron
• Scores: Splicing: ADA: 0.0001078
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 0.988
• 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)

ENSG00000226149 (HGNC:):

ACMG classification

Our verdict: Likely_benign. The variant received -4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.77).
• BP6: Variant 6-129473205-C-T is Benign according to our data. Variant chr6-129473205-C-T is described in ClinVar as Likely_benign. ClinVar VariationId is 543875.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
LAMA2	NM_000426.4	c.7301-9C>T		intron_variant	Intron 51 of 64	ENST00000421865.3	NP_000417.3
LAMA2	NM_001079823.2	c.7301-9C>T		intron_variant	Intron 51 of 63		NP_001073291.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
LAMA2	ENST00000421865.3	c.7301-9C>T		intron_variant	Intron 51 of 64	5	NM_000426.4	ENSP00000400365.2
LAMA2	ENST00000618192.5	c.7565-9C>T		intron_variant	Intron 52 of 65	5		ENSP00000480802.2
LAMA2	ENST00000617695.5	c.7301-9C>T		intron_variant	Intron 51 of 63	5		ENSP00000481744.2
ENSG00000226149	ENST00000665046.1	n.975+29400G>A		intron_variant	Intron 9 of 9

Frequencies

GnomAD3 genomes AF: 0.0000132 AC: 2 AN: 151908 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000483

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000140 AC: 2 AN: 1425988 Hom.: 0 Cov.: 27 AF XY: 0.00000141 AC XY: 1 AN XY: 711738

African (AFR) AF: 0.0000305 AC: 1 AN: 32738

American (AMR) AF: 0.00 AC: 0 AN: 44534

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25842

East Asian (EAS) AF: 0.00 AC: 0 AN: 39286

South Asian (SAS) AF: 0.00 AC: 0 AN: 85376

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52836

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5698

European-Non Finnish (NFE) AF: 9.25e-7 AC: 1 AN: 1080556

Other (OTH) AF: 0.00 AC: 0 AN: 59122

GnomAD4 genome AF: 0.0000132 AC: 2 AN: 151908 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74158

African (AFR) AF: 0.0000483 AC: 2 AN: 41382

American (AMR) AF: 0.00 AC: 0 AN: 15224

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5186

South Asian (SAS) AF: 0.00 AC: 0 AN: 4820

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10602

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 67904

Other (OTH) AF: 0.00 AC: 0 AN: 2090

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000227

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

LAMA2-related muscular dystrophy Benign:1

Sep 01, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.77
CADD	Benign	15
DANN	Benign	0.52
PhyloP100		0.99

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.00011
dbscSNV1_RF	Benign	0.0040
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: rs747783456; hg19: chr6-129794350;