rs7531245

chr1-218434221-A-C

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_Strong BP6_Very_Strong BS1 BS2

The NM_003238.6(TGFB2):c.643+7A>C variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00239 in 1,613,432 control chromosomes in the GnomAD database, including 88 homozygotes. In-silico tool predicts a benign outcome for this variant. 1/1 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.013 (43 hom., cov: 32)
  • Exomes 𝑓: 0.0013 (45 hom.)
• Consequence: TGFB2 NM_003238.6 splice_region, intron
• Scores: Splicing: ADA: 0.00001514
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:10
• Conservation: PhyloP100: -0.824

Genes affected

TGFB2 (HGNC:11768): (transforming growth factor beta 2) This gene encodes a secreted ligand of the TGF-beta (transforming growth factor-beta) superfamily of proteins. Ligands of this family bind various TGF-beta receptors leading to recruitment and activation of SMAD family transcription factors that regulate gene expression. The encoded preproprotein is proteolytically processed to generate a latency-associated peptide (LAP) and a mature peptide, and is found in either a latent form composed of a mature peptide homodimer, a LAP homodimer, and a latent TGF-beta binding protein, or in an active form consisting solely of the mature peptide homodimer. The mature peptide may also form heterodimers with other TGF-beta family members. Disruption of the TGF-beta/SMAD pathway has been implicated in a variety of human cancers. A chromosomal translocation that includes this gene is associated with Peters' anomaly, a congenital defect of the anterior chamber of the eye. Mutations in this gene may be associated with Loeys-Dietz syndrome. This gene encodes multiple isoforms that may undergo similar proteolytic processing. [provided by RefSeq, Aug 2016]

ACMG classification

Verdict is Benign. Variant got -20 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.85).
• BP6: Variant 1-218434221-A-C is Benign according to our data. Variant chr1-218434221-A-C is described in ClinVar as [Likely_benign]. Clinvar id is 139416.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-218434221-A-C is described in Lovd as [Benign]. Variant chr1-218434221-A-C is described in Lovd as [Likely_benign].
• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.013 (1982/152326) while in subpopulation AFR AF= 0.0447 (1857/41572). AF 95% confidence interval is 0.043. There are 43 homozygotes in gnomad4. There are 941 alleles in male gnomad4 subpopulation. This position pass quality control queck.
• BS2: High AC in GnomAd at 1970 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TGFB2	NM_003238.6	c.643+7A>C		splice_region_variant, intron_variant		ENST00000366930.9
TGFB2	NM_001135599.4	c.727+7A>C		splice_region_variant, intron_variant
TGFB2	NR_138148.2	n.2009+7A>C		splice_region_variant, intron_variant, non_coding_transcript_variant
TGFB2	NR_138149.2	n.2093+7A>C		splice_region_variant, intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TGFB2	ENST00000366930.9	c.643+7A>C		splice_region_variant, intron_variant		1	NM_003238.6	P1
TGFB2	ENST00000366929.4	c.727+7A>C		splice_region_variant, intron_variant		1
TGFB2	ENST00000479322.1	n.96A>C		non_coding_transcript_exon_variant	1/5	3
TGFB2	ENST00000488793.1	n.314A>C		non_coding_transcript_exon_variant	3/3	3

Frequencies

GnomAD3 genomes AF: 0.0129 AC: 1970 AN: 152208 Hom.: 42 Cov.: 32

Gnomad AFR AF: 0.0445

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00635

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000103

Gnomad OTH AF: 0.00955

GnomAD3 exomes AF: 0.00337 AC: 846 AN: 251076 Hom.: 20 AF XY: 0.00242 AC XY: 328 AN XY: 135686

Gnomad AFR exome AF: 0.0463

Gnomad AMR exome AF: 0.00211

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.000229

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000440

Gnomad OTH exome AF: 0.00131

GnomAD4 exome AF: 0.00128 AC: 1869 AN: 1461106 Hom.: 45 Cov.: 31 AF XY: 0.00107 AC XY: 781 AN XY: 726696

Gnomad4 AFR exome AF: 0.0459

Gnomad4 AMR exome AF: 0.00242

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.000313

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000135

Gnomad4 OTH exome AF: 0.00278

GnomAD4 genome AF: 0.0130 AC: 1982 AN: 152326 Hom.: 43 Cov.: 32 AF XY: 0.0126 AC XY: 941 AN XY: 74494

Gnomad4 AFR AF: 0.0447

Gnomad4 AMR AF: 0.00634

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000207

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.000103

Gnomad4 OTH AF: 0.00945

Alfa AF: 0.00850 Hom.: 13

Bravo AF: 0.0152

Asia WGS AF: 0.00260 AC: 9 AN: 3478

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:10

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Benign:4

Benign, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Aug 19, 2019	Variant summary: TGFB2 c.643+7A>C alters a non-conserved nucleotide located close to a canonical splice site and therefore could affect mRNA splicing, leading to a significantly altered protein sequence. 4/4 computational 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 0.0034 in 251076 control chromosomes in the gnomAD database, including 20 homozygotes. The observed variant frequency is approximately 270 fold of the estimated maximal expected allele frequency for a pathogenic variant in TGFB2 causing Aortopathy phenotype (1.3e-05), strongly suggesting that the variant is benign. To our knowledge, no occurrence of c.643+7A>C in individuals affected with Aortopathy and no experimental evidence demonstrating its impact on protein function have been reported. Co-occurrences with other pathogenic variant(s) have been reported at our laboratory (FBN1 c.349C>T, p.Q117*), providing supporting evidence for a benign role. Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as benign. Based on the evidence outlined above, the variant was classified as benign. -
Benign, criteria provided, single submitter	clinical testing	GeneDx	May 28, 2014	This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -
Benign, criteria provided, single submitter	clinical testing	PreventionGenetics, part of Exact Sciences	-	- -
Benign, no assertion criteria provided	clinical testing	Genome Diagnostics Laboratory, Amsterdam University Medical Center	-	- -

Loeys-Dietz syndrome 4 Benign:3

Benign, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 12, 2018	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 benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -
Benign, criteria provided, single submitter	clinical testing	Invitae	Jan 31, 2024	- -
Benign, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Oct 16, 2023	- -

Familial thoracic aortic aneurysm and aortic dissection Benign:1

Benign, criteria provided, single submitter

clinical testing

CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario

Jul 22, 2016

- -

Ehlers-Danlos syndrome Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Genome Diagnostics Laboratory, The Hospital for Sick Children

Jun 08, 2022

- -

not provided Benign:1

Likely benign, no assertion criteria provided

clinical testing

Laboratory of Diagnostic Genome Analysis, Leiden University Medical Center (LUMC)

-

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.85
Cadd	Benign	0.13
Dann	Benign	0.54

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.000015
SpliceAI score (max)		0.020		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs7531245; hg19: chr1-218607563;