chr15-48437920-G-A

Variant summary

Our verdict is Benign. The variant received -7 ACMG points: 0P and 7B. BP4_ModerateBP6BS1

The NM_000138.5(FBN1):​c.6164-3C>T variant causes a splice region, intron change. The variant allele was found at a frequency of 0.000218 in 1,613,444 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).

Frequency

Genomes: 𝑓 0.000092 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00023 ( 0 hom. )

Consequence

FBN1
NM_000138.5 splice_region, intron

Scores

2
Splicing: ADA: 0.07773
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:5

Conservation

PhyloP100: 6.53

Publications

1 publications found
Variant links:
Genes affected
FBN1 (HGNC:3603): (fibrillin 1) This gene encodes a member of the fibrillin family of proteins. The encoded preproprotein is proteolytically processed to generate two proteins including the extracellular matrix component fibrillin-1 and the protein hormone asprosin. Fibrillin-1 is an extracellular matrix glycoprotein that serves as a structural component of calcium-binding microfibrils. These microfibrils provide force-bearing structural support in elastic and nonelastic connective tissue throughout the body. Asprosin, secreted by white adipose tissue, has been shown to regulate glucose homeostasis. Mutations in this gene are associated with Marfan syndrome and the related MASS phenotype, as well as ectopia lentis syndrome, Weill-Marchesani syndrome, Shprintzen-Goldberg syndrome and neonatal progeroid syndrome. [provided by RefSeq, Apr 2016]
FBN1 Gene-Disease associations (from GenCC):
  • familial thoracic aortic aneurysm and aortic dissection
    Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
  • Marfan syndrome
    Inheritance: AD, AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, ClinGen, G2P, PanelApp Australia, Orphanet, Ambry Genetics
  • Acromicric dysplasia
    Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Ambry Genetics
  • progeroid and marfanoid aspect-lipodystrophy syndrome
    Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Orphanet
  • stiff skin syndrome
    Inheritance: AD Classification: STRONG, LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • Weill-Marchesani syndrome 2, dominant
    Inheritance: AD Classification: STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
  • geleophysic dysplasia
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • isolated ectopia lentis
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • neonatal Marfan syndrome
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Weill-Marchesani syndrome
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • ectopia lentis 1, isolated, autosomal dominant
    Inheritance: AD Classification: LIMITED Submitted by: G2P
  • Shprintzen-Goldberg syndrome
    Inheritance: AD, Unknown Classification: LIMITED, NO_KNOWN Submitted by: ClinGen, Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -7 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.2).
BP6
Variant 15-48437920-G-A is Benign according to our data. Variant chr15-48437920-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 200074.We mark this variant Benign, oryginal submission is: [Conflicting_classifications_of_pathogenicity].
BS1
Variant frequency is greater than expected in population sas. GnomAd4 allele frequency = 0.000092 (14/152206) while in subpopulation SAS AF = 0.00124 (6/4826). AF 95% confidence interval is 0.000541. There are 0 homozygotes in GnomAd4. There are 6 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FBN1NM_000138.5 linkc.6164-3C>T splice_region_variant, intron_variant Intron 50 of 65 ENST00000316623.10 NP_000129.3 P35555
FBN1NM_001406716.1 linkc.6164-3C>T splice_region_variant, intron_variant Intron 49 of 64 NP_001393645.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FBN1ENST00000316623.10 linkc.6164-3C>T splice_region_variant, intron_variant Intron 50 of 65 1 NM_000138.5 ENSP00000325527.5 P35555

Frequencies

GnomAD3 genomes
AF:
0.0000921
AC:
14
AN:
152088
Hom.:
0
Cov.:
32
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:
0.00124
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000118
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000876
AC:
22
AN:
251030
AF XY:
0.0000664
show subpopulations
Gnomad AFR exome
AF:
0.0000615
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:
0.000106
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000231
AC:
337
AN:
1461238
Hom.:
0
Cov.:
32
AF XY:
0.000220
AC XY:
160
AN XY:
726850
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33436
American (AMR)
AF:
0.0000224
AC:
1
AN:
44678
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26118
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39690
South Asian (SAS)
AF:
0.000383
AC:
33
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53258
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5760
European-Non Finnish (NFE)
AF:
0.000265
AC:
295
AN:
1111682
Other (OTH)
AF:
0.000116
AC:
7
AN:
60360
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.453
Heterozygous variant carriers
0
17
35
52
70
87
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
20
40
60
80
100
<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:
0.0000920
AC:
14
AN:
152206
Hom.:
0
Cov.:
32
AF XY:
0.0000806
AC XY:
6
AN XY:
74404
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41538
American (AMR)
AF:
0.00
AC:
0
AN:
15272
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5176
South Asian (SAS)
AF:
0.00124
AC:
6
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10590
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.000118
AC:
8
AN:
68012
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.546
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.0000818
Hom.:
0
Bravo
AF:
0.0000453
EpiCase
AF:
0.000218
EpiControl
AF:
0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:5
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection Benign:2
Oct 26, 2018
Color Diagnostics, LLC DBA Color Health
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

May 30, 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. -

Marfan syndrome Uncertain:1
Feb 05, 2018
Baylor Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was determined to be of uncertain significance according to ACMG Guidelines, 2015 [PMID:25741868]. -

not specified Benign:1
Oct 24, 2023
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: FBN1 c.6164-3C>T alters a 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 8.8e-05 in 251030 control chromosomes, predominantly at a frequency of 0.00029 within the South Asian subpopulation in the gnomAD database. The observed variant frequency within South Asian control individuals in the gnomAD database is approximately 3 fold of the estimated maximal expected allele frequency for a pathogenic variant in FBN1 causing Marfan Syndrome (0.00011), strongly suggesting that the variant is a benign polymorphism found primarily in populations of South Asian origin. To our knowledge, no occurrence of c.6164-3C>T in individuals affected with Marfan Syndrome and no experimental evidence demonstrating its impact on protein function have been reported. Five submitters have cited clinical-significance assessments for this variant to ClinVar after 2014 and classified as likely benign (n=3) and VUS (n=2). Based on the evidence outlined above, the variant was classified as likely benign. -

not provided Benign:1
Mar 02, 2021
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is associated with the following publications: (PMID: 25834947, 32123317) -

Marfan syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection Benign:1
Jan 29, 2025
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
-0.20
CADD
Benign
16
DANN
Benign
0.96
PhyloP100
6.5
Mutation Taster
=67/33
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.078
dbscSNV1_RF
Benign
0.11
Splicevardb
1.0
SpliceAI score (max)
0.080
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: rs571365493; hg19: chr15-48730117; API