{"id":"51e67120-bbbd-50f6-b94a-cc3819432e29","stable_key":"548ab9d6-3a9b-5bed-879c-17d03813b636:transport-slc52a2-normal-plasma","predicate":"can-be-impaired-despite","statement":"The child with compound SLC52A2 L123P/L339P variants had normal measured plasma riboflavin, FMN and FAD despite a transport-associated neurologic disorder.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"a80d3820-d8b7-58eb-8e3f-606cae34b75b","mechanism_event_label":"Normal plasma flavins did not exclude a cellular transport defect.","subject":{"id":"67aa820f-85b6-583e-a350-5a09c7b36eea","slug":"slc52a2","display_name":"Riboflavin transporter 2 / SLC52A2","entity_type_key":"protein"},"object":{"id":"e751f872-8f38-5187-968f-34920f3385c8","slug":"plasma-flavin-concentrations","display_name":"Plasma riboflavin, FMN and FAD concentrations","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"a80d3820-d8b7-58eb-8e3f-606cae34b75b","stable_key":"548ab9d6-3a9b-5bed-879c-17d03813b636:transport-slc52a2-normal-plasma-event","event_type":"observed_intervention","label":"Normal plasma flavins did not exclude a cellular transport defect.","description":"The child with compound SLC52A2 L123P/L339P variants had normal measured plasma riboflavin, FMN and FAD despite a transport-associated neurologic disorder.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"bbb15e98-19e3-50e4-a83e-787a1c461fd0","slug":"slc52a2-l123p","display_name":"SLC52A2 L123P variant","entity_type_key":"protein_state"},"role":"variant","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"ac119507-638f-58bd-9065-2049162d8b10","slug":"slc52a2-l339p","display_name":"SLC52A2 L339P variant","entity_type_key":"protein_state"},"role":"variant","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"86eb1eee-a8d1-539c-8c17-0911f69b6f1b","slug":"riboflavin","display_name":"Riboflavin (vitamin B2)","entity_type_key":"small_molecule"},"role":"measured-flavin","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"d3eacf85-1a35-546d-bd30-161474dd9691","slug":"fmn","display_name":"Flavin mononucleotide","entity_type_key":"small_molecule"},"role":"measured-flavin","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"e2cd7179-f218-54e8-9ce9-7a836ae35fac","slug":"fad","display_name":"FAD","entity_type_key":"small_molecule"},"role":"measured-flavin","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""},{"entity":{"id":"67aa820f-85b6-583e-a350-5a09c7b36eea","slug":"slc52a2","display_name":"Riboflavin transporter 2 / SLC52A2","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":5,"notes":""},{"entity":{"id":"e751f872-8f38-5187-968f-34920f3385c8","slug":"plasma-flavin-concentrations","display_name":"Plasma riboflavin, FMN and FAD concentrations","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":6,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; 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Study references: [transport-slc52a2-disease-2012] Impaired riboflavin transport due to missense mutations in SLC52A2 causes Brown-Vialetto-Van Laere syndrome (2012). https://pmc.ncbi.nlm.nih.gov/articles/PMC3470687/ DOI: 10.1007/s10545-012-9513-y","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"4f7c9578-82bf-5e2d-b5c4-72a79fb4f6af","stable_key":"import-548ab9d6-3a9b-5bed-879c-17d03813b636","title":"Riboflavin: mechanisms, deficiency and nutrient interactions (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"680cb6bc8249877f2410f551807f10d390fdd719014137d7414ba3420e29228d","revision_id":"7a61e299-908d-5372-860b-99ed190f9d7a","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}