The goal of this observational study is to learn about the genetic background for the development of optic disc drusen. The main question is:

• Can one or more candidate genes be found?

Participants will have a blood sample taken and answer a questionnaire.

The study is an international collaboration between University of Utah, University of Sydney, University of Valladolid, and University of Copenhagen. Patients with Optic disc drusen from 15 known optic disc drusen-families from different countries (USA, Australia, Spain and Denmark) are participating in this study.

Blood samples are drawn from each patient and their affected and unaffected family members, and DNA will be extracted. The investigators will do an Optical coherence tomography-scan (according to ODDS Consortium guidelines), and the participant will be asked to fill out the Visual Function Questionnaire (VFQ-25) including four additional questions about optic disc drusen.

The etiology of optic disc drusen will be analyzed with a Whole Exome Sequencing (WES), with the use of Next Generation Sequencing (NGS). Prior to WES, all participants will receive genetic counseling by a consultant to ensure awareness of possible secondary genetic findings.

Inclusion Criteria:

• Adult patients over the age of 18, who are capable of giving consent
• Diagnosis of optic disc drusen and a minimum of 3 optic disc drusen-affected family members

Exclusion Criteria:

• Less than 3 affected family members
• Under the age of 18 or mentally disabled

Families with ODD

Data will only be shared with the project responsible unit