1-171635993-C-A

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_Strong PM2

The NM_000261.2(MYOC):c.1447G>T(p.Glu483Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: MYOC NM_000261.2 stop_gained
• Clinical Significance: Uncertain significance reviewed by expert panel U:1
• Conservation: PhyloP100: 3.33

Genes affected

MYOC (HGNC:7610): (myocilin) MYOC encodes the protein myocilin, which is believed to have a role in cytoskeletal function. MYOC is expressed in many occular tissues, including the trabecular meshwork, and was revealed to be the trabecular meshwork glucocorticoid-inducible response protein (TIGR). The trabecular meshwork is a specialized eye tissue essential in regulating intraocular pressure, and mutations in MYOC have been identified as the cause of hereditary juvenile-onset open-angle glaucoma. [provided by RefSeq, Jul 2008]

MYOCOS (HGNC:53429): (myocilin opposite strand)

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 5 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYOC	NM_000261.2	c.1447G>T	p.Glu483Ter	stop_gained	3/3	ENST00000037502.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYOC	ENST00000037502.11	c.1447G>T	p.Glu483Ter	stop_gained	3/3	1	NM_000261.2	P1
MYOCOS	ENST00000637303.1	c.235-2637C>A		intron_variant		5		A2
MYOC	ENST00000638471.1	c.*785G>T		3_prime_UTR_variant, NMD_transcript_variant	4/4	5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: reviewed by expert panel

Submissions by phenotype

Open-angle glaucoma Uncertain:1

Uncertain significance, reviewed by expert panel

curation

ClinGen Glaucoma Variant Curation Expert Panel

Apr 03, 2023

The c.1447G>T variant in MYOC is predicted to cause a change in the length of the protein due to the insertion of a terminating codon instead of the usual Methionine at amino acid 483. This variant is predicted to cause a deletion of < 10% of the protein within the conserved olfactomedin domain, meeting PM4_Supporting. This variant was not found in any population of gnomAD (v2.1.1), meeting the <= 0.0001 threshold set for PM2_Supporting in a population of at least 10,000 alleles. There was no computational or functional evidence predicting a damaging or benign impact of this variant on MYOC function. Only 1 proband with primary open angle glaucoma had been reported (PMID: 10196380), not meeting the >= 2 probands threshold required to meet PS4_Supporting. In summary, this variant met the criteria to receive a score of 2 and to be classified as a variant of uncertain significance (uncertain significance classification range -1 to 5) for primary open angle glaucoma based on the ACMG/AMP criteria met, as specified by the ClinGen Glaucoma VCEP (v1, 12 Oct 2021): PM2_Supporting, PM4_Supporting. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.55	D
BayesDel_noAF	Pathogenic	0.55
Cadd	Pathogenic	38
Dann	Uncertain	1.0
Eigen	Pathogenic	0.85
Eigen_PC	Pathogenic	0.67
FATHMM_MKL	Benign	0.45	N
MutationTaster	Benign	1.0	D
Vest4		0.83
GERP RS		3.9

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr1-171605133;