Version 2.77

Term Description

Phenylalanine/Tyrosine is a primary marker for Phenylketonuria, Hyperphenylalaninemia (variant, benign), Disorders of biopterin biosynthesis and Disorders of biopterin regeneration.
Source: Regenstrief LOINC

Part Descriptions

LP15792-2   Phenylalanine
Phenylalanine is an essential alpha-amino acid. It exists in two forms, a D and an L form, which are enantiomers (mirror-image molecules) of each other. It has a benzyl side chain and its name comes from its chemical structures that consists of a phenyl group substituted for one of the hydrogens in the side chain of alanine. Because of its phenyl group, phenylalanine is an aromatic compound that at room temperature exists as a white, powdery solid. L -phenylalanine (LPA) is an electrically-neutral amino acid and its enantiomer, D -phenylalanine (DPA), can be synthesized artificially. L -phenylalanine can also be converted into L -tyrosine, another one of the twenty protein-forming amino acids. Copyright Text is available under the Creative Commons Attribution/Share-Alike License. See for details. Source: Wikipedia, Phenylalanine (Wikipedia)

LP32175-9   Tyrosine
Tyrosine (from the Greek tyros, meaning cheese, as it was first discovered in cheese[ citationneeded ]), 4-hydroxyphenylalanine, or 2-amino-3(4-hydroxyphenyl)-propanoic acid, is one of the 20 amino acids that are used by cells to synthesize proteins. It has a phenol side chain with a hydroxyl group. Upon the location of the hydroxyl group, there are three structural isomers of Tyr, namely para-Tyr (p-Tyr), meta-Tyr (m-Tyr) and ortho-Tyr (o-Tyr). Enzymatically, only the first isomer (p-Tyr) is produced from L-Phe by the Phe-hydroxylase enzyme. The other two isoforms, m-Tyr and o-Tyr can be produced as a consequence of free radical attack on Phe in states with increased oxidative stress. Copyright Text is available under the Creative Commons Attribution/Share-Alike License. See for details. Source: Wikipedia, Tyrosine (Wikipedia)

LP32175-9   Tyrosine
A non-essential amino acid. In animals it is synthesized from PHENYLALANINE. It is also the precursor of EPINEPHRINE; THYROID HORMONES; and melanin. Source: National Library of Medicine, MeSH 2006

Fully-Specified Name


Additional Names

Short Name
Phe/Tyr SerPl-sRto
Display Name
Phenylalanine/Tyrosine [Molar ratio]
Consumer Name Alpha Get Info
Phenylalanine/Tyrosine, Blood

Basic Attributes

First Released
Version 2.07
Last Updated
Version 2.70
Order vs. Observation

Language Variants Get Info

Tag Language Translation
de-AT German (Austria) Synonyms: Phenylalanin/Tyrosin-Ratio
es-AR Spanish (Argentina) fenilalanina/tirosina:relación de concentración de la sustancia:punto en el tiempo:suero/plasma:cuantitativo:
es-ES Spanish (Spain) Fenilalanina/Tirosina:Relacion de Sustancia:Punto temporal:Suero o Plasma:Qn:
Synonyms: Cuantitativo
es-MX Spanish (Mexico) Fenilalanina / Tirosina:Proporción de sustancia:Punto temporal:Suero o Plasma:Cuantitativo:
fr-CA French (Canada) Phénylalanine/Tyrosine:Ratio de substance:Temps ponctuel:Sérum/Plasma:Quantitatif:
fr-FR French (France) Phénylalanine/tyrosine:Moles ratio:Ponctuel:Sérum/Plasma:Numérique:
fr-BE French (Belgium) Phénylalanine/Tyrosine:Ratio de substance:Temps ponctuel:Sérum/Plasma:Quantitatif:
it-IT Italian (Italy) Fenilalanina/Tirosina:Srto:Pt:Siero/Plasma:Qn:
Synonyms: Chimica Plasma Punto nel tempo (episodio) Rapporto di sostanza Siero Siero o Plasma
ko-KR Korean (Korea, Republic Of) 페닐알라닌/티로신:물질구성비:검사시점:혈청/혈장:정량:
nl-NL Dutch (Netherlands) fenylalanine/tyrosine:molaire verhouding:moment:serum of plasma:kwantitatief:
pl-PL Polish (Poland) Fenyloalanina/tyrozyna:współczynnik molowy:punkt w czasie:surowica lub osocze:ilościowy:
pt-BR Portuguese (Brazil) Fenilalanina/Tirosina:SCrto:Pt:Sor/Plas:Qn:
Synonyms: ; Phe; PPA; Tyr; Phe+Tyr; Phe/Tyr; sRto; Substance concentration ratio; Point in time; Random; SerPl; SerPlas; SerP; Serum; SR; Plasma; Pl; Plsm; Quantitative; QNT; Quant; Quan; Chemistry
ru-RU Russian (Russian Federation) Фенилаланин/Тирозин:МольОтн:ТчкВрм:Сыв/Плаз:Колич:
Synonyms: Количественный Мольная доля;Молярная доля;Отношение концентраций Плазма Сыворотка Сыворотка или Плазма Точка во времени;Момент
tr-TR Turkish (Turkey) Fenilalanin/Tirozin:SOrn:Zmlı:Ser/Plaz:Kant:
Synonyms: SubsOranı
zh-CN Chinese (China) 苯丙氨酸/酪氨酸:物质的量比率:时间点:血清/血浆:定量型:
Synonyms: 3-对羟苯基丙氨酸;Tyr Phe;PPA;苯基丙氨酸 Phe+Tyr;Phe+Tyrosine;苯丙氨酸与酪氨酸;苯基丙氨酸+酪氨酸;苯基丙氨酸与酪氨酸 Tyr 化学;化学检验项目;化学检验项目类;化学类;化学试验;非刺激耐受型化学检验项目;非刺激耐受型化学检验项目类;非刺激耐受型化学试验;非刺激耐受型化学试验类 可用数量表示的;定量性;数值型;数量型;连续数值型标尺 时刻;随机;随意;瞬间 物质的量比值;物质的量比;摩尔比;摩尔比率;摩尔比值 血清或血浆

Example Units

Unit Source
{Ratio} Example UCUM Units

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