The c.1309T>C variant in MYOC is a missense variant predicted to cause substitution of Tyrosine by Histidine at amino acid 437 (p.Tyr437His). 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 = 0.966, which met the ≥ 0.7 threshold for PP3, predicting a damaging effect on MYOC function. Previous studies (PMIDs: 16466712 and 35196929) demonstrated that the Tyr437His protein had increased insolubility and 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. 39 segregations in 3 families, with juvenile or primary open angle glaucoma (JOAG or POAG), have been reported (PMIDs: 9535666, 30612094), which fulfilled PP1_Strong (≥ 7 meioses in > 1 family). 6 probands with JOAG or POAG have been reported carrying this variant (PMIDs: 10196380, 9792882, 30612094), which met PS4_Moderate (≥ 6 probands). In summary, this variant met the criteria to receive a score of 10 and to be classified as pathogenic (pathogenic classification ≥ 10) 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, PS4_Moderate, PP3, PM2_Supporting.