rs765676702

Variant summary

Our verdict is Benign. The variant received -10 ACMG points: 0P and 10B. BP4_StrongBP6BP7BS2

The NM_001999.4(FBN2):​c.7137T>G​(p.Leu2379Leu) variant causes a splice region, synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000292 in 1,611,726 control chromosomes in the GnomAD database, with no homozygous occurrence. 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 Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. L2379L) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000030 ( 0 hom. )

Consequence

FBN2
NM_001999.4 splice_region, synonymous

Scores

2
Splicing: ADA: 0.0001503
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:4

Conservation

PhyloP100: -0.245

Publications

0 publications found
Variant links:
Genes affected
FBN2 (HGNC:3604): (fibrillin 2) The protein encoded by this gene is a component of connective tissue microfibrils and may be involved in elastic fiber assembly. Mutations in this gene cause congenital contractural arachnodactyly. [provided by RefSeq, Jul 2008]
FBN2 Gene-Disease associations (from GenCC):
  • congenital contractural arachnodactyly
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: PanelApp Australia, Orphanet, Labcorp Genetics (formerly Invitae), G2P, Genomics England PanelApp
  • carpal tunnel syndrome
    Inheritance: AD Classification: LIMITED Submitted by: Franklin by Genoox
  • familial thoracic aortic aneurysm and aortic dissection
    Inheritance: AD Classification: LIMITED Submitted by: ClinGen
  • macular degeneration, early-onset
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -10 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.47).
BP6
Variant 5-128280193-A-C is Benign according to our data. Variant chr5-128280193-A-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 416903.
BP7
Synonymous conserved (PhyloP=-0.245 with no splicing effect.
BS2
High AC in GnomAdExome4 at 44 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FBN2NM_001999.4 linkc.7137T>G p.Leu2379Leu splice_region_variant, synonymous_variant Exon 56 of 65 ENST00000262464.9 NP_001990.2
FBN2XM_017009228.3 linkc.6984T>G p.Leu2328Leu splice_region_variant, synonymous_variant Exon 55 of 64 XP_016864717.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FBN2ENST00000262464.9 linkc.7137T>G p.Leu2379Leu splice_region_variant, synonymous_variant Exon 56 of 65 1 NM_001999.4 ENSP00000262464.4
FBN2ENST00000703783.1 linkn.3921T>G splice_region_variant, non_coding_transcript_exon_variant Exon 31 of 38

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152224
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000438
AC:
11
AN:
250884
AF XY:
0.0000369
show subpopulations
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:
0.0000881
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000301
AC:
44
AN:
1459502
Hom.:
0
Cov.:
29
AF XY:
0.0000275
AC XY:
20
AN XY:
726196
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33422
American (AMR)
AF:
0.00
AC:
0
AN:
44720
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26108
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39574
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86206
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53052
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5758
European-Non Finnish (NFE)
AF:
0.0000387
AC:
43
AN:
1110352
Other (OTH)
AF:
0.00
AC:
0
AN:
60310
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.460
Heterozygous variant carriers
0
3
6
9
12
15
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<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:
0.0000197
AC:
3
AN:
152224
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74372
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41460
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5200
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68032
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.442
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<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:
0.0000333
Hom.:
0
Bravo
AF:
0.0000302
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:4
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Congenital contractural arachnodactyly Uncertain:1Benign:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
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, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Jul 27, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Benign:1
Nov 11, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: FBN2 c.7137T>G (p.Leu2379Leu) alters a conserved nucleotide located close to a canonical splice site and therefore could affect mRNA splicing, leading to a significantly altered protein sequence. Consensus agreement among computation tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 4.4e-05 in 250884 control chromosomes, predominantly at a frequency of 8.8e-05 within the Non-Finnish European subpopulation in the gnomAD database. The observed variant frequency within Non-Finnish European control individuals in the gnomAD database is approximately 70 - fold of the estimated maximal expected allele frequency for a pathogenic variant in FBN2 causing aortopathy phenotype (1.3e-06). c.7137T>G has been reported in the literature in at least an individual affected with FBN2-related conditions (example: Renner_2019). This report however, does not provide unequivocal conclusions about association of the variant with aortopathy. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publication has been ascertained in the context of this evaluation (PMID: 30675029). ClinVar contains an entry for this variant (Variation ID: 416903). Based on the evidence outlined above, the variant was classified as likely benign. -

Familial thoracic aortic aneurysm and aortic dissection Benign:1
Apr 04, 2024
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

not provided Benign:1
Jul 10, 2020
GeneDx
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
-0.47
CADD
Benign
2.4
DANN
Benign
0.71
PhyloP100
-0.24

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.00015
dbscSNV1_RF
Benign
0.0060
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: rs765676702; hg19: chr5-127615885; API