{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,10]],"date-time":"2026-10-10T16:24:01Z","timestamp":1791649441697,"version":"4.3.4"},"reference-count":124,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,5,15]],"date-time":"2026-05-15T00:00:00Z","timestamp":1778803200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100019280","name":"Corporaci\u00f3n Ecuatoriana para el Desarrollo de la Investigaci\u00f3n y la Academia","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100019280","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Mol. Biosci."],"abstract":"<jats:p>Disorders of the phenylalanine\u2013tyrosine\u2013catecholamine axis are a clinically relevant group of neurometabolic conditions in which pathogenic variants in key enzymes impair dopamine and norepinephrine biosynthesis. Patients may present with movement disorders, autonomic dysfunction, developmental delay, and related neurobehavioral manifestations. In this narrative review, we synthesize the main enzymatic defects across the axis, focusing on phenylalanine hydroxylase, tyrosine hydroxylase, aromatic L-amino acid decarboxylase, and dopamine beta-hydroxylase. We describe how diagnostic practice has evolved from isolated biochemical assays to integrated approaches that link clinical phenotyping with targeted biochemical profiling and molecular confirmation. Genetic testing now supports diagnosis, treatment planning, and family counseling, while chromatographic and mass spectrometry-based methods remain essential for quantifying amino acids and neurotransmitter-related metabolites. We also discuss emerging biosensor-based strategies as a potential route to decentralized and minimally invasive monitoring.<\/jats:p>","DOI":"10.3389\/fmolb.2026.1767655","type":"journal-article","created":{"date-parts":[[2026,5,15]],"date-time":"2026-05-15T04:28:41Z","timestamp":1778819321000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Phenylalanine\u2013tyrosine\u2013catecholamine axis disorders: pathways, molecular diagnosis, therapeutics, and emerging translational monitoring technologies"],"prefix":"10.3389","volume":"13","author":[{"given":"Martina Isabella","family":"Armas Samaniego","sequence":"first","affiliation":[{"name":"Departamento de Biotecnolog\u00eda, Colegio de Ciencias Biol\u00f3gicas y Ambientales, Universidad San Francisco de Quito","place":["Quito, Pichincha, Ecuador"]},{"name":"Escuela de Medicina, Colegio de Ciencias de la Salud, Universidad San Francisco de Quito","place":["Quito, Pichincha, Ecuador"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Benjamin","family":"Arias-Almeida","sequence":"additional","affiliation":[{"name":"Instituto de Microbiolog\u00eda, Colegio de Ciencias Biol\u00f3gicas y Ambientales, Universidad San Francisco de Quito","place":["Quito, Pichincha, Ecuador"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andr\u00e9s","family":"Le\u00f3n-Pi\u00f1eiros","sequence":"additional","affiliation":[{"name":"Instituto de Microbiolog\u00eda, Colegio de Ciencias Biol\u00f3gicas y Ambientales, Universidad San Francisco de Quito","place":["Quito, Pichincha, Ecuador"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jorge G.","family":"Figueroa","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica, Facultad de Ciencias Exactas y Naturales, Universidad T\u00e9cnica Particular de Loja","place":["Loja, Ecuador"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrea","family":"Vargas-Freire","sequence":"additional","affiliation":[{"name":"Departamento de Biotecnolog\u00eda, Colegio de Ciencias Biol\u00f3gicas y Ambientales, Universidad San Francisco de Quito","place":["Quito, Pichincha, Ecuador"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Melissa","family":"L\u00f3pez","sequence":"additional","affiliation":[{"name":"Instituto de Microbiolog\u00eda, Colegio de Ciencias Biol\u00f3gicas y Ambientales, Universidad San Francisco de Quito","place":["Quito, Pichincha, Ecuador"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Natal\u00ed","family":"Solano-Cueva","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica, Facultad de Ciencias Exactas y Naturales, Universidad T\u00e9cnica Particular de Loja","place":["Loja, Ecuador"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Juan Carlos","family":"Collantes","sequence":"additional","affiliation":[{"name":"Departamento de Biotecnolog\u00eda, Colegio de Ciencias Biol\u00f3gicas y Ambientales, Universidad San Francisco de Quito","place":["Quito, Pichincha, Ecuador"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mar\u00eda de Lourdes","family":"Huiracocha-Tutiven","sequence":"additional","affiliation":[{"name":"Carrera de Medicina, Facultad de Ciencias M\u00e9dicas, Universidad de Cuenca","place":["Cuenca, Ecuador"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gabriele Davide","family":"Bigoni-Ord\u00f3\u00f1ez","sequence":"additional","affiliation":[{"name":"Carrera de Laboratorio Cl\u00ednico, Facultad de Ciencias M\u00e9dicas, Universidad de Cuenca","place":["Cuenca, Ecuador"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Juan Carlos","family":"Pozo-Palacios","sequence":"additional","affiliation":[{"name":"Carrera de Medicina, Facultad de Ciencias M\u00e9dicas, Universidad de Cuenca","place":["Cuenca, Ecuador"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vanessa","family":"Romero","sequence":"additional","affiliation":[{"name":"Escuela de Medicina, Colegio de Ciencias de la Salud, Universidad San Francisco de Quito","place":["Quito, Pichincha, Ecuador"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,5,15]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"1390133","DOI":"10.3389\/fnut.2024.1390133","article-title":"Navigating phenylketonuria management to improve it in Latin America: a systematic literature review and applicability analysis","volume":"11","author":"Aguirre","year":"","journal-title":"Front. 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