1-209634627-G-C

Variant names:

• chr1-209634627-G-C
• rs1130667
• NM_000228.3:c.384C>G

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 2P and 7B. PM2 BP4_Strong BP6_Moderate BP7

The NM_000228.3(LAMB3):​c.384C>G​(p.Pro128Pro) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,560 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 (★). Synonymous variant affecting the same amino acid position (i.e. P128P) has been classified as Benign.

• Frequency:
  • Genomes: not found (cov: 30)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: LAMB3 NM_000228.3 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -4.01
• Publications: 16 publications found

Genes affected

LAMB3 (HGNC:6490): (laminin subunit beta 3) The product encoded by this gene is a laminin that belongs to a family of basement membrane proteins. This protein is a beta subunit laminin, which together with an alpha and a gamma subunit, forms laminin-5. Mutations in this gene cause epidermolysis bullosa junctional Herlitz type, and generalized atrophic benign epidermolysis bullosa, diseases that are characterized by blistering of the skin. Multiple alternatively spliced transcript variants that encode the same protein have been found for this gene. [provided by RefSeq, Jul 2008]

LAMB3 Gene-Disease associations (from GenCC):

• junctional epidermolysis bullosa

  Inheritance: AR Classification: DEFINITIVE Submitted by: Myriad Women’s Health
• junctional epidermolysis bullosa Herlitz type

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Orphanet, Laboratory for Molecular Medicine
• junctional epidermolysis bullosa, non-Herlitz type

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Genomics England PanelApp, Ambry Genetics
• amelogenesis imperfecta type 1A

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
• amelogenesis imperfecta type 1

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• generalized junctional epidermolysis bullosa non-Herlitz type

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.68).
• BP6: Variant 1-209634627-G-C is Benign according to our data. Variant chr1-209634627-G-C is described in ClinVar as Likely_benign. ClinVar VariationId is 2134013.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=-4.01 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
LAMB3	NM_000228.3	c.384C>G	p.Pro128Pro	synonymous_variant	Exon 6 of 23	ENST00000356082.9	NP_000219.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
LAMB3	ENST00000356082.9	c.384C>G	p.Pro128Pro	synonymous_variant	Exon 6 of 23	1	NM_000228.3	ENSP00000348384.3
LAMB3	ENST00000367030.7	c.384C>G	p.Pro128Pro	synonymous_variant	Exon 6 of 23	1		ENSP00000355997.3
LAMB3	ENST00000391911.5	c.384C>G	p.Pro128Pro	synonymous_variant	Exon 5 of 22	1		ENSP00000375778.1
LAMB3	ENST00000415782.1	c.384C>G	p.Pro128Pro	synonymous_variant	Exon 6 of 6	2		ENSP00000388960.1

Frequencies

GnomAD3 genomes Cov.: 30

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460560 Hom.: 0 Cov.: 39 AF XY: 0.00 AC XY: 0 AN XY: 726524

⚠️ 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: 33466

American (AMR) AF: 0.00 AC: 0 AN: 44610

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26116

East Asian (EAS) AF: 0.00 AC: 0 AN: 39632

South Asian (SAS) AF: 0.00 AC: 0 AN: 86130

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53294

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5752

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111228

Other (OTH) AF: 0.0000166 AC: 1 AN: 60332

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 30

Alfa AF: 0.00 Hom.: 6126

Bravo AF: 0.00000756

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Benign:1

May 05, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.68
CADD	Benign	0.10
DANN	Benign	0.52
PhyloP100		-4.0
Mutation Taster		=100/0	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		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: rs1130667; hg19: chr1-209807972;