3-187220269-A-C

Position:

• chr3-187220269-A-C

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP6

The NM_001879.6(MASP1):​c.1910-8T>G variant causes a splice region, splice polypyrimidine tract, 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 (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: MASP1 NM_001879.6 splice_region, splice_polypyrimidine_tract, intron
• Scores: Splicing: ADA: 0.00004228
• Clinical Significance: Likely benign no assertion criteria provided B:1
• Conservation: PhyloP100: 0.470

Genes affected

MASP1 (HGNC:6901): (MBL associated serine protease 1) This gene encodes a serine protease that functions as a component of the lectin pathway of complement activation. The complement pathway plays an essential role in the innate and adaptive immune response. The encoded protein is synthesized as a zymogen and is activated when it complexes with the pathogen recognition molecules of lectin pathway, the mannose-binding lectin and the ficolins. This protein is not directly involved in complement activation but may play a role as an amplifier of complement activation by cleaving complement C2 or by activating another complement serine protease, MASP-2. The encoded protein is also able to cleave fibrinogen and factor XIII and may may be involved in coagulation. A splice variant of this gene which lacks the serine protease domain functions as an inhibitor of the complement pathway. Alternate splicing results in multiple transcript variants.[provided by RefSeq, Apr 2010]

ACMG classification

Verdict is Likely_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.88).
• BP6: Variant 3-187220269-A-C is Benign according to our data. Variant chr3-187220269-A-C is described in ClinVar as [Likely_benign]. Clinvar id is 3036392.Status of the report is no_assertion_criteria_provided, 0 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MASP1	NM_001879.6	c.1910-8T>G		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		ENST00000337774.10	NP_001870.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MASP1	ENST00000337774.10	c.1910-8T>G		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		1	NM_001879.6	ENSP00000336792	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: no assertion criteria provided

Submissions by phenotype

MASP1-related disorder Benign:1

Likely benign, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Jul 20, 2020

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.88
CADD	Benign	7.4
DANN	Benign	0.67

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.000042
dbscSNV1_RF	Benign	0.0040
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

No publications associated with this variant yet.

Other links and lift over

hg19: chr3-186938057;