disease arises from structure disease arises from alteration in structure 20q13 (Human) Duane-radial ray syndrome Okihiro syndrome due to 20q13 microdeletion https://github.com/monarch-initiative/mondo/issues/3664 Okihiro syndrome due to del(20)(q13) Okihiro syndrome due to monosomy 20q13 UMLS:C5679682 GARD:0020787 MONDO:0016863 Orphanet:261638 Duane-radial ray syndrome due to monosomy 20q13 MEDGEN:1826026 partial deletion of the long arm of chromosome 20