3-187250279-C-G

Variant names:

• chr3-187250279-C-G
• NM_139125.4:c.1062G>C
• MASP1 p.Thr354Thr

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 2P and 3B. PM2 BP4_Moderate BP7

The NM_139125.4(MASP1):​c.1062G>C​(p.Thr354Thr) variant causes a synonymous 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. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. T354T) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: MASP1 NM_139125.4 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -5.87
• Publications: 0 publications found

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]

MASP1 Gene-Disease associations (from GenCC):

• 3MC syndrome 1

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• 3MC syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.37).
• BP7: Synonymous conserved (PhyloP=-5.87 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_139125.4. 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
	MASP1	NM_139125.4	MANE Select	c.1062G>C	p.Thr354Thr	synonymous	Exon 8 of 11	NP_624302.1	P48740-2
	MASP1	NM_001879.6	MANE Plus Clinical	c.1062G>C	p.Thr354Thr	synonymous	Exon 8 of 16	NP_001870.3
	MASP1	NM_001031849.3		c.1062G>C	p.Thr354Thr	synonymous	Exon 8 of 9	NP_001027019.1	P48740-3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MASP1	ENST00000296280.11	TSL:1 MANE Select	c.1062G>C	p.Thr354Thr	synonymous	Exon 8 of 11	ENSP00000296280.7	P48740-2
	MASP1	ENST00000337774.10	TSL:1 MANE Plus Clinical	c.1062G>C	p.Thr354Thr	synonymous	Exon 8 of 16	ENSP00000336792.5	P48740-1
	MASP1	ENST00000392472.6	TSL:1	c.723G>C	p.Thr241Thr	synonymous	Exon 7 of 10	ENSP00000376264.2	P48740-4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.37
CADD	Benign	0.25
DANN	Benign	0.63
PhyloP100		-5.9

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr3-186968067;