chr3-187220985-C-A

Variant names:

• chr3-187220985-C-A
• rs75655422
• NM_001879.6:c.1909+50G>T

Variant summary

Our verdict is Benign. The variant received -14 ACMG points: 0P and 14B. BP4_Strong BP6_Moderate BS1 BS2

The NM_001879.6(MASP1):​c.1909+50G>T variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000983 in 1,503,172 control chromosomes in the GnomAD database, including 13 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★).

• Frequency:
  • Genomes: 𝑓 0.0051 (9 hom., cov: 31)
  • Exomes 𝑓: 0.00052 (4 hom.)
• Consequence: MASP1 NM_001879.6 intron
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -1.29
• 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), PanelApp Australia
• 3MC syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Benign. The variant received -14 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.88).
• BP6: Variant 3-187220985-C-A is Benign according to our data. Variant chr3-187220985-C-A is described in ClinVar as Likely_benign. ClinVar VariationId is 1328784.Status of the report is criteria_provided_single_submitter, 1 stars.
• BS1: Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.00511 (778/152336) while in subpopulation AFR AF = 0.018 (750/41564). AF 95% confidence interval is 0.017. There are 9 homozygotes in GnomAd4. There are 372 alleles in the male GnomAd4 subpopulation. Median coverage is 31. This position passed quality control check.
• BS2: High Homozygotes in GnomAd4 at 9 AR gene

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001879.6. 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_001879.6	MANE Plus Clinical	c.1909+50G>T		intron	N/A	NP_001870.3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MASP1	ENST00000337774.10	TSL:1 MANE Plus Clinical	c.1909+50G>T		intron	N/A	ENSP00000336792.5	P48740-1

Frequencies

GnomAD3 genomes AF: 0.00509 AC: 775 AN: 152218 Hom.: 9 Cov.: 31

Gnomad AFR AF: 0.0180

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00124

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000882

Gnomad OTH AF: 0.00144

GnomAD2 exomes AF: 0.00129 AC: 320 AN: 248840 AF XY: 0.000914

Gnomad AFR exome AF: 0.0173

Gnomad AMR exome AF: 0.000667

Gnomad ASJ exome AF: 0.000199

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.000107

Gnomad OTH exome AF: 0.000656

GnomAD4 exome AF: 0.000518 AC: 700 AN: 1350836 Hom.: 4 Cov.: 20 AF XY: 0.000392 AC XY: 266 AN XY: 678276

African (AFR) AF: 0.0174 AC: 543 AN: 31252

American (AMR) AF: 0.000696 AC: 31 AN: 44514

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25460

East Asian (EAS) AF: 0.00 AC: 0 AN: 39142

South Asian (SAS) AF: 0.0000477 AC: 4 AN: 83842

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53090

Middle Eastern (MID) AF: 0.00201 AC: 10 AN: 4974

European-Non Finnish (NFE) AF: 0.0000455 AC: 46 AN: 1011910

Other (OTH) AF: 0.00117 AC: 66 AN: 56652

GnomAD4 genome AF: 0.00511 AC: 778 AN: 152336 Hom.: 9 Cov.: 31 AF XY: 0.00499 AC XY: 372 AN XY: 74488

African (AFR) AF: 0.0180 AC: 750 AN: 41564

American (AMR) AF: 0.00124 AC: 19 AN: 15312

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5188

South Asian (SAS) AF: 0.00 AC: 0 AN: 4826

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10624

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.0000882 AC: 6 AN: 68032

Other (OTH) AF: 0.00142 AC: 3 AN: 2112

Alfa AF: 0.00255 Hom.: 1

Bravo AF: 0.00542

Asia WGS AF: 0.000866 AC: 3 AN: 3478

ClinVar

ClinVar submissions as Germline

Significance: Likely benign

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	-	1	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.88
CADD	Benign	0.61
DANN	Benign	0.49
PhyloP100		-1.3
Mutation Taster		=100/0	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs75655422; hg19: chr3-186938773;