1-171636173-T-C

Variant names:

• chr1-171636173-T-C
• rs74315336
• NM_000261.2:c.1267A>G

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PP3 PS3_Moderate PS4_Supporting PM2_Supporting PP1_Strong

This summary comes from the ClinGen Evidence Repository: The c.1267A>G variant in MYOC is a missense variant predicted to cause substitution of Lysine by Glutamic Acid at amino acid 423 (p.Lys423Glu). 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. The REVEL score = 0.876, which met the ≥ 0.7 threshold for PP3, predicting a damaging effect on MYOC function. A previous study (PMID:16466712) demonstrated that the Lys423Glu protein had reduced secretion levels compared to wild type myocilin protein and met the OddsPath threshold for PS3_Moderate (> 4.3), indicating that this variant did impact protein function. 80 segregations in 2 families, with juvenile or primary open angle glaucoma (JOAG or POAG), have been reported (PMIDs: 12860809, 9697688), which fulfilled PP1_Strong (≥7 meioses in >1 family). 4 probands with JOAG or POAG have been reported carrying this variant (PMIDs: 30484747, 12189160, 12860809, 9697688), which met PS4_Supporting (≥ 2 probands). In summary, this variant met the criteria to receive a score of 9 and to be classified as likely pathogenic (likely pathogenic classification range 6 to 9) for juvenile open angle glaucoma based on the ACMG/AMP criteria met, as specified by the ClinGen Glaucoma VCEP (v1, 12 Oct 2021): PP1_Strong, PS3_Moderate, PP3, PS4_Supporting, PM2_Supporting LINK:https://erepo.genome.network/evrepo/ui/classification/CA119178/MONDO:0020367/019

• Frequency: Genomes: not found (cov: 32)
• Consequence: MYOC NM_000261.2 missense
• Clinical Significance: Likely pathogenic reviewed by expert panel P:2
• Conservation: PhyloP100: 6.24
• Publications: 36 publications found

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

Our verdict: Likely_pathogenic. The variant received 9 ACMG points.

• PS3: For more information check the summary or visit ClinGen Evidence Repository.
• PS4: For more information check the summary or visit ClinGen Evidence Repository.
• PM2: For more information check the summary or visit ClinGen Evidence Repository.
• PP1: For more information check the summary or visit ClinGen Evidence Repository.
• PP3: For more information check the summary or visit ClinGen Evidence Repository.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000261.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MYOC	NM_000261.2	MANE Select	c.1267A>G	p.Lys423Glu	missense	Exon 3 of 3	NP_000252.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MYOC	ENST00000037502.11	TSL:1 MANE Select	c.1267A>G	p.Lys423Glu	missense	Exon 3 of 3	ENSP00000037502.5
	MYOC	ENST00000638471.1	TSL:5	n.*605A>G		non_coding_transcript_exon	Exon 4 of 4	ENSP00000491206.1
	MYOC	ENST00000638471.1	TSL:5	n.*605A>G		3_prime_UTR	Exon 4 of 4	ENSP00000491206.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:2

Revision: reviewed by expert panel

Submissions by phenotype

Glaucoma 1, open angle, A Pathogenic:1

Aug 01, 1998

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

Glaucoma of childhood Pathogenic:1

May 09, 2022

ClinGen Glaucoma Variant Curation Expert Panel

Significance: Likely pathogenic

Review Status: reviewed by expert panel

Collection Method: curation

The c.1267A>G variant in MYOC is a missense variant predicted to cause substitution of Lysine by Glutamic Acid at amino acid 423 (p.Lys423Glu). 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. The REVEL score = 0.876, which met the >= 0.7 threshold for PP3, predicting a damaging effect on MYOC function. A previous study (PMID: 16466712) demonstrated that the Lys423Glu protein had reduced secretion levels compared to wild type myocilin protein and met the OddsPath threshold for PS3_Moderate (> 4.3), indicating that this variant did impact protein function. 80 segregations in 2 families, with juvenile or primary open angle glaucoma (JOAG or POAG), have been reported (PMIDs: 12860809, 9697688), which fulfilled PP1_Strong (>=7 meioses in >1 family). 4 probands with JOAG or POAG have been reported carrying this variant (PMIDs: 30484747, 12189160, 12860809, 9697688), which met PS4_Supporting (>= 2 probands). In summary, this variant met the criteria to receive a score of 9 and to be classified as likely pathogenic (likely pathogenic classification range 6 to 9) for juvenile open angle glaucoma based on the ACMG/AMP criteria met, as specified by the ClinGen Glaucoma VCEP (v1, 12 Oct 2021): PP1_Strong, PS3_Moderate, PP3, PS4_Supporting, PM2_Supporting

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.96
BayesDel_addAF	Pathogenic	0.36	D
BayesDel_noAF	Pathogenic	0.28
CADD	Uncertain	26
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.98	D
Eigen	Uncertain	0.58
Eigen_PC	Uncertain	0.42
FATHMM_MKL	Uncertain	0.85	D
LIST_S2	Uncertain	0.90	D
M_CAP	Uncertain	0.11	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	0.85	D
MutationAssessor	Pathogenic	4.0	H
PhyloP100		6.2
PrimateAI	Uncertain	0.60	T
PROVEAN	Uncertain	-4.0	D
REVEL	Pathogenic	0.88
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0050	D
Polyphen		1.0	D
Vest4		0.94
MutPred		0.89		Loss of methylation at K423 (P = 0.0013)
MVP		0.99
MPC		0.85
ClinPred		1.0	D
GERP RS		3.9
Varity_R		0.95
gMVP		0.92
Mutation Taster		=43/57	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs74315336; hg19: chr1-171605313;