18-23931208-G-T

Variant summary

Our verdict is Benign. The variant received -20 ACMG points: 0P and 20B. BP4_StrongBP6_Very_StrongBS1BS2

The NM_198129.4(LAMA3):​c.8576+7G>T variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00338 in 1,610,880 control chromosomes in the GnomAD database, including 11 homozygotes. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.0024 ( 1 hom., cov: 32)
Exomes 𝑓: 0.0035 ( 10 hom. )

Consequence

LAMA3
NM_198129.4 splice_region, intron

Scores

2
Splicing: ADA: 0.00002224
2

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:5

Conservation

PhyloP100: -0.524

Publications

11 publications found
Variant links:
Genes affected
LAMA3 (HGNC:6483): (laminin subunit alpha 3) The protein encoded by this gene belongs to the laminin family of secreted molecules. Laminins are heterotrimeric molecules that consist of alpha, beta, and gamma subunits that assemble through a coiled-coil domain. Laminins are essential for formation and function of the basement membrane and have additional functions in regulating cell migration and mechanical signal transduction. This gene encodes an alpha subunit and is responsive to several epithelial-mesenchymal regulators including keratinocyte growth factor, epidermal growth factor and insulin-like growth factor. Mutations in this gene have been identified as the cause of Herlitz type junctional epidermolysis bullosa and laryngoonychocutaneous syndrome. Alternative splicing and alternative promoter usage result in multiple transcript variants. [provided by RefSeq, Dec 2014]
LAMA3 Gene-Disease associations (from GenCC):
  • junctional epidermolysis bullosa
    Inheritance: AR Classification: DEFINITIVE Submitted by: Myriad Women’s Health
  • laryngo-onycho-cutaneous syndrome
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Orphanet
  • junctional epidermolysis bullosa Herlitz type
    Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Orphanet
  • junctional epidermolysis bullosa, non-Herlitz type
    Inheritance: AR Classification: STRONG Submitted by: PanelApp Australia, Genomics England PanelApp
  • generalized junctional epidermolysis bullosa non-Herlitz type
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -20 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.74).
BP6
Variant 18-23931208-G-T is Benign according to our data. Variant chr18-23931208-G-T is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 326334.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.00236 (360/152308) while in subpopulation NFE AF = 0.004 (272/68038). AF 95% confidence interval is 0.00361. There are 1 homozygotes in GnomAd4. There are 166 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
BS2
High Homozygotes in GnomAdExome4 at 10 AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
LAMA3NM_198129.4 linkc.8576+7G>T splice_region_variant, intron_variant Intron 65 of 74 ENST00000313654.14 NP_937762.2 Q16787-2
LAMA3NM_000227.6 linkc.3749+7G>T splice_region_variant, intron_variant Intron 28 of 37 ENST00000269217.11 NP_000218.3 Q16787-1A0A0A6YYF2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
LAMA3ENST00000313654.14 linkc.8576+7G>T splice_region_variant, intron_variant Intron 65 of 74 1 NM_198129.4 ENSP00000324532.8 Q16787-2
LAMA3ENST00000269217.11 linkc.3749+7G>T splice_region_variant, intron_variant Intron 28 of 37 1 NM_000227.6 ENSP00000269217.5 Q16787-1A0A0A6YYF2

Frequencies

GnomAD3 genomes
AF:
0.00237
AC:
360
AN:
152190
Hom.:
1
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000676
Gnomad AMI
AF:
0.00548
Gnomad AMR
AF:
0.00137
Gnomad ASJ
AF:
0.00403
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000415
Gnomad FIN
AF:
0.00141
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00400
Gnomad OTH
AF:
0.00143
GnomAD2 exomes
AF:
0.00243
AC:
612
AN:
251424
AF XY:
0.00235
show subpopulations
Gnomad AFR exome
AF:
0.000677
Gnomad AMR exome
AF:
0.00113
Gnomad ASJ exome
AF:
0.00446
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.00125
Gnomad NFE exome
AF:
0.00404
Gnomad OTH exome
AF:
0.00277
GnomAD4 exome
AF:
0.00349
AC:
5089
AN:
1458572
Hom.:
10
Cov.:
34
AF XY:
0.00339
AC XY:
2458
AN XY:
725886
show subpopulations
African (AFR)
AF:
0.000538
AC:
18
AN:
33432
American (AMR)
AF:
0.00110
AC:
49
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00471
AC:
123
AN:
26116
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39690
South Asian (SAS)
AF:
0.000499
AC:
43
AN:
86180
European-Finnish (FIN)
AF:
0.00167
AC:
89
AN:
53410
Middle Eastern (MID)
AF:
0.00104
AC:
6
AN:
5764
European-Non Finnish (NFE)
AF:
0.00415
AC:
4606
AN:
1108984
Other (OTH)
AF:
0.00255
AC:
154
AN:
60280
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.503
Heterozygous variant carriers
0
262
523
785
1046
1308
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
182
364
546
728
910
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00236
AC:
360
AN:
152308
Hom.:
1
Cov.:
32
AF XY:
0.00223
AC XY:
166
AN XY:
74466
show subpopulations
African (AFR)
AF:
0.000674
AC:
28
AN:
41546
American (AMR)
AF:
0.00137
AC:
21
AN:
15310
Ashkenazi Jewish (ASJ)
AF:
0.00403
AC:
14
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.000415
AC:
2
AN:
4814
European-Finnish (FIN)
AF:
0.00141
AC:
15
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00400
AC:
272
AN:
68038
Other (OTH)
AF:
0.00142
AC:
3
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.505
Heterozygous variant carriers
0
21
42
64
85
106
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
Variant carriers
0
10
20
30
40
50
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00368
Hom.:
6537

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Benign:3
-
Laboratory of Diagnostic Genome Analysis, Leiden University Medical Center (LUMC)
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Jan 23, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Laryngo-onycho-cutaneous syndrome Benign:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Junctional epidermolysis bullosa gravis of Herlitz Benign:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.74
CADD
Benign
0.31
DANN
Benign
0.41
PhyloP100
-0.52
Mutation Taster
=100/0
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.000022
dbscSNV1_RF
Benign
0.0
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

Publications

Other links and lift over

dbSNP: rs1258107; hg19: chr18-21511172; API