chr7-140734776-A-T

Variant names:

• chr7-140734776-A-T
• rs397516900
• NM_001374258.1:c.2248-6T>A

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 2P and 6B. PM2 BP4_Strong BP6_Moderate

The NM_001374258.1(BRAF):​c.2248-6T>A variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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 Likely benign (★).

• Frequency: Genomes: not found (cov: 28)
• Consequence: BRAF NM_001374258.1 splice_region, intron
• Scores: Splicing: ADA: 0.0007039
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 2.67
• Publications: 0 publications found

Genes affected

BRAF (HGNC:1097): (B-Raf proto-oncogene, serine/threonine kinase) This gene encodes a protein belonging to the RAF family of serine/threonine protein kinases. This protein plays a role in regulating the MAP kinase/ERK signaling pathway, which affects cell division, differentiation, and secretion. Mutations in this gene, most commonly the V600E mutation, are the most frequently identified cancer-causing mutations in melanoma, and have been identified in various other cancers as well, including non-Hodgkin lymphoma, colorectal cancer, thyroid carcinoma, non-small cell lung carcinoma, hairy cell leukemia and adenocarcinoma of lung. Mutations in this gene are also associated with cardiofaciocutaneous, Noonan, and Costello syndromes, which exhibit overlapping phenotypes. A pseudogene of this gene has been identified on the X chromosome. [provided by RefSeq, Aug 2017]

BRAF Gene-Disease associations (from GenCC):

• cardiofaciocutaneous syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• cardiofaciocutaneous syndrome 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), PanelApp Australia, Ambry Genetics, G2P, Genomics England PanelApp
• LEOPARD syndrome 3

  Inheritance: AD Classification: DEFINITIVE, STRONG, LIMITED Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics, Genomics England PanelApp
• Noonan syndrome 7

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), PanelApp Australia, G2P, Ambry Genetics, Genomics England PanelApp
• Noonan syndrome

  Inheritance: AD Classification: MODERATE Submitted by: ClinGen
• Noonan syndrome with multiple lentigines

  Inheritance: AD Classification: SUPPORTIVE, LIMITED Submitted by: ClinGen, Orphanet
• anaplastic astrocytoma

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
• Costello syndrome

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Likely_benign. The variant received -4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.79).
• BP6: Variant 7-140734776-A-T is Benign according to our data. Variant chr7-140734776-A-T is described in ClinVar as Likely_benign. ClinVar VariationId is 44822.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BRAF	NM_001374258.1	c.2248-6T>A		splice_region_variant, intron_variant	Intron 18 of 19	ENST00000644969.2	NP_001361187.1
BRAF	NM_004333.6	c.2128-6T>A		splice_region_variant, intron_variant	Intron 17 of 17	ENST00000646891.2	NP_004324.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRAF	ENST00000644969.2	c.2248-6T>A		splice_region_variant, intron_variant	Intron 18 of 19		NM_001374258.1	ENSP00000496776.1
BRAF	ENST00000646891.2	c.2128-6T>A		splice_region_variant, intron_variant	Intron 17 of 17		NM_004333.6	ENSP00000493543.1

Frequencies

GnomAD3 genomes Cov.: 28

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 28

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Benign:1

Mar 07, 2011

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

2128-6T>A in exon 18 in BRAF: The 2128-6T>A variant in BRAF has not been previou sly reported in the literature or been identified in our laboratory. This varian t is located in the 3' splice region but does not affect the invariant -1 and -2 positions. While positions -3 and -5 to -12 are part of the splicing consensus sequence and variants involving these positions sometimes affect splicing, patho genic splicing variants have not been previously associated with BRAF in individ uals in Noonan spectrum disorders. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.79
CADD	Benign	13
DANN	Benign	0.55
PhyloP100		2.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.00070
dbscSNV1_RF	Benign	0.11
SpliceAI score (max)		0.14		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: rs397516900; hg19: chr7-140434576;