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(2006). https://pubmed.ncbi.nlm.nih.gov/16400613/ DOI: 10.1086/500092","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"CoQ synthesis","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"57090b5f-1465-575a-b62c-95279b3836c0","evidence_kind":"source_excerpt","locator":"Lines 229-240","start_line":229,"end_line":240,"excerpt":"### coq10-coq2-loss\nA homozygous COQ2 variant caused severe impairment of CoQ10 synthesis in patient fibroblasts.\nCondition category: machinery_impairment\nnutrient_topic: Coenzyme Q10 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Having the building blocks does not help if the enzyme that joins them is defective.\norganism: Human siblings\ntissue_or_cell_type: CoQ synthesis\nexperimental_model: Family sequencing and fibroblast tracer assays\nlimitations: Rare primary deficiency; sequence numbering follows the original publication.\nexposure: Homozygous COQ2 missense variant\nevidence_span: {\"source_cache\": \"artifacts/coq10-research/16400613.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"bd16a213ac563cf32b275cdee32ba3082e6c296cf9129e0930e2f96f0d2dc72a\", \"start_char\": 0, \"end_char\": 1000, \"text_sha256\": \"bd16a213ac563cf32b275cdee32ba3082e6c296cf9129e0930e2f96f0d2dc72a\"}\n[coq10-p16400613] A mutation in para-hydroxybenzoate-polyprenyl transferase (COQ2) causes primary coenzyme Q10 deficiency. 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