chr5-128335997-C-T

Variant names:

• chr5-128335997-C-T
• rs778784375
• NM_001999.4:c.3715G>A

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 4P and 1B. PM1 PM2 BP4

The NM_001999.4(FBN2):​c.3715G>A​(p.Gly1239Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,754 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G1239V) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: FBN2 NM_001999.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.17
• Publications: 1 publications found

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: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), G2P, Orphanet
• carpal tunnel syndrome

  Inheritance: AD Classification: LIMITED Submitted by: Franklin by Genoox
• macular degeneration, early-onset

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
• familial thoracic aortic aneurysm and aortic dissection

  Inheritance: Unknown Classification: LIMITED Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 5 benign, 10 uncertain in NM_001999.4
• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.33559698).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001999.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FBN2	NM_001999.4	MANE Select	c.3715G>A	p.Gly1239Ser	missense	Exon 28 of 65	NP_001990.2	P35556-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FBN2	ENST00000262464.9	TSL:1 MANE Select	c.3715G>A	p.Gly1239Ser	missense	Exon 28 of 65	ENSP00000262464.4	P35556-1
	FBN2	ENST00000939405.1		c.3616G>A	p.Gly1206Ser	missense	Exon 27 of 64	ENSP00000609464.1
	FBN2	ENST00000939404.1		c.3562G>A	p.Gly1188Ser	missense	Exon 27 of 64	ENSP00000609463.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 250984 AF XY: 0.00

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: 0.00000882

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461754 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727180

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39692

South Asian (SAS) AF: 0.00 AC: 0 AN: 86250

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53346

Middle Eastern (MID) AF: 0.000173 AC: 1 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111968

Other (OTH) AF: 0.00 AC: 0 AN: 60392

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000508 Hom.: 0

Bravo AF: 0.00000378

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Congenital contractural arachnodactyly (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.068
BayesDel_addAF	Uncertain	0.11	D
BayesDel_noAF	Benign	-0.090
CADD	Benign	23
DANN	Uncertain	0.99
DEOGEN2	Benign	0.33	T
Eigen	Benign	-0.28
Eigen_PC	Benign	-0.063
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Uncertain	0.87	D
M_CAP	Uncertain	0.088	D
MetaRNN	Benign	0.34	T
MetaSVM	Uncertain	-0.13	T
MutationAssessor	Benign	-0.49	N
PhyloP100		2.2
PrimateAI	Uncertain	0.56	T
PROVEAN	Benign	-1.8	N
REVEL	Uncertain	0.42
Sift	Benign	0.40	T
Sift4G	Benign	1.0	T
Polyphen		0.074	B
Vest4		0.34
MutPred		0.39		Gain of glycosylation at G1239 (P = 0.0705)
MVP		0.45
MPC		0.35
ClinPred		0.38	T
GERP RS		3.8
Varity_R		0.14
gMVP		0.67
Mutation Taster		=44/56	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
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

Other links and lift over

dbSNP: rs778784375; hg19: chr5-127671689;