rs12324002

Variant summary

Our verdict is Benign. The variant received -17 ACMG points: 3P and 20B. PM1PP2BP4_StrongBP6_Very_StrongBS1BS2

The NM_000138.5(FBN1):​c.986T>C​(p.Ile329Thr) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00124 in 1,614,086 control chromosomes in the GnomAD database, including 33 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 Benign (★★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I329V) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0068 ( 17 hom., cov: 32)
Exomes 𝑓: 0.00066 ( 16 hom. )

Consequence

FBN1
NM_000138.5 missense, splice_region

Scores

1
7
8
Splicing: ADA: 0.7362
2

Clinical Significance

Benign reviewed by expert panel U:1B:21

Conservation

PhyloP100: 7.52

Publications

11 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 -17 ACMG points.

PM1
In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 15 uncertain in NM_000138.5
PP2
Missense variant in the FBN1 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 1311 curated pathogenic missense variants (we use a threshold of 10). The gene has 112 curated benign missense variants. Gene score misZ: 5.0644 (above the threshold of 3.09). Trascript score misZ: 8.1787 (above the threshold of 3.09). GenCC associations: The gene is linked to Marfan syndrome, Weill-Marchesani syndrome 2, dominant, progeroid and marfanoid aspect-lipodystrophy syndrome, geleophysic dysplasia, Shprintzen-Goldberg syndrome, stiff skin syndrome, familial thoracic aortic aneurysm and aortic dissection, isolated ectopia lentis, ectopia lentis 1, isolated, autosomal dominant, Acromicric dysplasia, neonatal Marfan syndrome, Weill-Marchesani syndrome.
BP4
Computational evidence support a benign effect (MetaRNN=0.0101932585).
BP6
Variant 15-48526132-A-G is Benign according to our data. Variant chr15-48526132-A-G is described in ClinVar as Benign. ClinVar VariationId is 36133.Status of the report is reviewed_by_expert_panel, 3 stars.
BS1
Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.00676 (1030/152278) while in subpopulation AFR AF = 0.0236 (982/41552). AF 95% confidence interval is 0.0224. There are 17 homozygotes in GnomAd4. There are 481 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
BS2
High Homozygotes in GnomAd4 at 17 AD,AR,Unknown gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FBN1NM_000138.5 linkc.986T>C p.Ile329Thr missense_variant, splice_region_variant Exon 9 of 66 ENST00000316623.10 NP_000129.3 P35555
FBN1NM_001406716.1 linkc.986T>C p.Ile329Thr missense_variant, splice_region_variant Exon 8 of 65 NP_001393645.1
LOC124903488XR_007064628.1 linkn.-119A>G upstream_gene_variant

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FBN1ENST00000316623.10 linkc.986T>C p.Ile329Thr missense_variant, splice_region_variant Exon 9 of 66 1 NM_000138.5 ENSP00000325527.5 P35555

Frequencies

GnomAD3 genomes
AF:
0.00674
AC:
1025
AN:
152160
Hom.:
17
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0236
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00216
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:
0.0000588
Gnomad OTH
AF:
0.00526
GnomAD2 exomes
AF:
0.00163
AC:
410
AN:
251412
AF XY:
0.00113
show subpopulations
Gnomad AFR exome
AF:
0.0234
Gnomad AMR exome
AF:
0.000549
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000264
Gnomad OTH exome
AF:
0.000489
GnomAD4 exome
AF:
0.000659
AC:
964
AN:
1461808
Hom.:
16
Cov.:
32
AF XY:
0.000510
AC XY:
371
AN XY:
727208
show subpopulations
African (AFR)
AF:
0.0245
AC:
821
AN:
33478
American (AMR)
AF:
0.000760
AC:
34
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39684
South Asian (SAS)
AF:
0.0000812
AC:
7
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.00139
AC:
8
AN:
5766
European-Non Finnish (NFE)
AF:
0.00000360
AC:
4
AN:
1111964
Other (OTH)
AF:
0.00149
AC:
90
AN:
60386
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.477
Heterozygous variant carriers
0
58
117
175
234
292
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
26
52
78
104
130
<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:
0.00676
AC:
1030
AN:
152278
Hom.:
17
Cov.:
32
AF XY:
0.00646
AC XY:
481
AN XY:
74466
show subpopulations
African (AFR)
AF:
0.0236
AC:
982
AN:
41552
American (AMR)
AF:
0.00216
AC:
33
AN:
15300
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3464
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10614
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68018
Other (OTH)
AF:
0.00521
AC:
11
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.502
Heterozygous variant carriers
0
46
93
139
186
232
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
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
Alfa
AF:
0.00253
Hom.:
12
Bravo
AF:
0.00766
ESP6500AA
AF:
0.0234
AC:
103
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.00229
AC:
278
Asia WGS
AF:
0.00202
AC:
7
AN:
3478

ClinVar

Significance: Benign
Submissions summary: Uncertain:1Benign:21
Revision: reviewed by expert panel
LINK: link

Submissions by phenotype

Marfan syndrome Uncertain:1Benign:6
May 28, 2019
Mendelics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Sep 26, 2023
ClinGen FBN1 Variant Curation Expert Panel, ClinGen
Significance:Benign
Review Status:reviewed by expert panel
Collection Method:curation

NM_000138.5 c.986T>C is a missense variant in FBN1 predicted to cause a substitution of an isoleucine by a threonine at amino acid 329 (p.Ile329Thr). This variant has been identified in numerous individuals with diagnoses or suspicion of Marfan syndrome in both the published literature and internal databases (PP4; PMIDs: 19293843, 24793577; Bichat, Mayo, UZG, UZA); however, in at least 2 of these cases, another pathogenic variant in FBN1 was also present (BP2; Bichat). This variant has been previously reported in ClinVar as likely benign or benign by more than 15 laboratories (Variation ID: 36133). It is present in gnomAD v3.1.2 at a frequency of 2.36% (977/41430 alleles) in the African/African American sub-population and is in the homozygous state in 17 total individuals (BA1; https://gnomad.broadinstitute.org/). Computational prediction tools and conservation analysis is unclear about a predicted impact of this variant. In summary, this variant meets criteria to be classified as benign for Marfan syndrome based on the ACMG/AMP criteria applied, as specified by the ClinGen FBN1 VCEP: BA1, BP2, PP4. The pathogenic evidence code PP4 was not considered to be in conflict with this conclusion. -

Feb 05, 2024
All of Us Research Program, National Institutes of Health
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Nov 07, 2017
Center for Medical Genetics Ghent, University of Ghent
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Feb 02, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. The evidence from the literature, in combination with allele frequency data from public databases where available, was sufficient to determine this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

Jan 27, 2012
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Nov 01, 2016
Center for Human Genetics, Inc, Center for Human Genetics, Inc
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Familial thoracic aortic aneurysm and aortic dissection Benign:4
Aug 02, 2016
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Mar 09, 2018
Color Diagnostics, LLC DBA Color Health
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jul 20, 2015
Ambry Genetics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as 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. -

Feb 02, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases allowed determination this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

not specified Benign:2
Sep 22, 2014
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Ile329Thr in exon 9 of FBN1: This variant is not expected to have clinical signi ficance because it has been identified in 2.3% (103/4394) of African American ch romosomes by the NHLBI Exome Sequencing Project (http://evs.gs.washington.edu/EV S/; dbSNP rs12324002). -

Dec 03, 2014
Eurofins Ntd Llc (ga)
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Benign:2
Dec 17, 2018
GeneDx
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is associated with the following publications: (PMID: 24793577, 19293843, 27153395, 26332594) -

Apr 21, 2023
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Stiff skin syndrome Benign:1
Feb 02, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases allowed determination this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

Weill-Marchesani syndrome Benign:1
Feb 02, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases allowed determination this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

Geleophysic dysplasia Benign:1
Feb 02, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases allowed determination this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

Acromicric dysplasia Benign:1
Feb 02, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases allowed determination this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

Marfan syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection Benign:1
Jan 30, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Connective tissue disorder Benign:1
Aug 01, 2019
Genome Diagnostics Laboratory, The Hospital for Sick Children
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Ectopia lentis 1, isolated, autosomal dominant Benign:1
Feb 02, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases allowed determination this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.18
BayesDel_addAF
Benign
-0.28
T
BayesDel_noAF
Benign
-0.15
CADD
Uncertain
24
DANN
Uncertain
0.99
Eigen
Benign
0.012
Eigen_PC
Uncertain
0.24
FATHMM_MKL
Pathogenic
1.0
D
LIST_S2
Benign
0.82
T
MetaRNN
Benign
0.010
T
MetaSVM
Uncertain
-0.19
T
PhyloP100
7.5
PrimateAI
Uncertain
0.49
T
PROVEAN
Uncertain
-3.7
D
REVEL
Uncertain
0.47
Sift
Uncertain
0.025
D
Sift4G
Benign
0.094
T
Vest4
0.77
MVP
0.49
MPC
0.69
ClinPred
0.068
T
GERP RS
6.0
Mutation Taster
=47/53
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.74
dbscSNV1_RF
Benign
0.58
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: rs12324002; hg19: chr15-48818329; API