has material basis in germline mutation in NOG proximal symphalangism proximal symphalangism 1A https://github.com/monarch-initiative/mondo/issues/6338 https://www.malacards.org/card/proximal_symphalangism_1 https://www.malacards.org/card/symphalangism_proximal_1a symphalangism, proximal, type 1A SYM1A Sym1 MEDGEN:811492 GARD:0025229 symphalangism, proximal, 1A UMLS:C3714899 hereditary absence of the proximal interphalangeal joints OMIM:185800 DOID:0080787 MONDO:0020733 Cushing symphalangism NOG-related symphalangism spectrum disorder