21-45453154-T-C

Variant names:

• chr21-45453154-T-C
• rs62216320
• NM_001379500.1:c.107-15088T>C

Variant summary

Our verdict is Benign. The variant received -14 ACMG points: 0P and 14B. BP4_Strong BP6_Moderate BA1

The NM_001379500.1(COL18A1):​c.107-15088T>C variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.13 in 150,196 control chromosomes in the GnomAD database, including 1,449 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★).

• Frequency: Genomes: 𝑓 0.13 (1449 hom., cov: 34)
• Consequence: COL18A1 NM_001379500.1 intron
• Clinical Significance: Benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -0.904
• Publications: 2 publications found

Genes affected

COL18A1 (HGNC:2195): (collagen type XVIII alpha 1 chain) This gene encodes the alpha chain of type XVIII collagen. This collagen is one of the multiplexins, extracellular matrix proteins that contain multiple triple-helix domains (collagenous domains) interrupted by non-collagenous domains. A long isoform of the protein has an N-terminal domain that is homologous to the extracellular part of frizzled receptors. Proteolytic processing at several endogenous cleavage sites in the C-terminal domain results in production of endostatin, a potent antiangiogenic protein that is able to inhibit angiogenesis and tumor growth. Mutations in this gene are associated with Knobloch syndrome. The main features of this syndrome involve retinal abnormalities, so type XVIII collagen may play an important role in retinal structure and in neural tube closure. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Dec 2014]

COL18A1 Gene-Disease associations (from GenCC):

• Knobloch syndrome 1

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

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Laboratory for Molecular Medicine, Orphanet
• hereditary glaucoma, primary closed-angle

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

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

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.8).
• BP6: Variant 21-45453154-T-C is Benign according to our data. Variant chr21-45453154-T-C is described in ClinVar as Benign. ClinVar VariationId is 1231975.Status of the report is criteria_provided_single_submitter, 1 stars.
• BA1: GnomAd4 highest subpopulation (EAS) allele frequency at 95% confidence interval = 0.205 is higher than 0.05.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001379500.1. 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
	COL18A1	NM_001379500.1	MANE Select	c.107-15088T>C		intron	N/A	NP_001366429.1	P39060-2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	COL18A1	ENST00000651438.1	MANE Select	c.107-15088T>C		intron	N/A	ENSP00000498485.1	P39060-2
	COL18A1	ENST00000859062.1		c.107-2591T>C		intron	N/A	ENSP00000529121.1
	COL18A1	ENST00000930602.1		c.107-15088T>C		intron	N/A	ENSP00000600661.1

Frequencies

GnomAD3 genomes AF: 0.130 AC: 19533 AN: 150082 Hom.: 1449 Cov.: 34

Gnomad AFR AF: 0.197

Gnomad AMI AF: 0.151

Gnomad AMR AF: 0.110

Gnomad ASJ AF: 0.159

Gnomad EAS AF: 0.216

Gnomad SAS AF: 0.106

Gnomad FIN AF: 0.119

Gnomad MID AF: 0.140

Gnomad NFE AF: 0.0911

Gnomad OTH AF: 0.124

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome AF: 0.130 AC: 19550 AN: 150196 Hom.: 1449 Cov.: 34 AF XY: 0.132 AC XY: 9703 AN XY: 73472

African (AFR) AF: 0.197 AC: 7835 AN: 39860

American (AMR) AF: 0.110 AC: 1667 AN: 15168

Ashkenazi Jewish (ASJ) AF: 0.159 AC: 550 AN: 3470

East Asian (EAS) AF: 0.216 AC: 1112 AN: 5160

South Asian (SAS) AF: 0.106 AC: 509 AN: 4792

European-Finnish (FIN) AF: 0.119 AC: 1257 AN: 10574

Middle Eastern (MID) AF: 0.144 AC: 42 AN: 292

European-Non Finnish (NFE) AF: 0.0911 AC: 6182 AN: 67880

Other (OTH) AF: 0.124 AC: 259 AN: 2090

Alfa AF: 0.126 Hom.: 136

Bravo AF: 0.131

ClinVar

ClinVar submissions

Significance: 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	-0.80
CADD	Benign	1.6
DANN	Benign	0.54
PhyloP100		-0.90
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.0
Mutation Taster		=100/0	polymorphism (auto)

Splicing

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

Other links and lift over

dbSNP: rs62216320; hg19: chr21-46873068;