Acronyms and Abbreviations

Abstract

n many fields today abbreviations and acronyms are common. They provide a useful tool for shortening long words or expression in order to save time and space. Some well-known general examples are DVD (digital versatile disc), UNICEF (United Nations International Children’s Emergency Fund), NASA (National Aeronautics and Space Administration), and UN (United Nations). Abbreviations are extensively used in the scientific and medical communities. It is common practice to use abbreviations for long names of many clinical diseases and procedures, and for scientific techniques that have to be repeated many times in medical or scientific papers, posters, and oral presentations. This can cause substantial communication difficulties for individuals who are not familiar with English abbreviations in their field. The example below is meaningless to individuals who are not familiar with the abbreviations used.

These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

In many fields today abbreviations and acronyms are common. They provide a useful tool for shortening long words or expression in order to save time and space. Some well-known general examples are DVD (digital versatile disc), UNICEF (United Nations International Children’s Emergency Fund), NASA (National Aeronautics and Space Administration), and UN (United Nations). Abbreviations are extensively used in the scientific and medical communities. It is common practice to use abbreviations for long names of many clinical diseases and procedures, and for scientific techniques that have to be repeated many times in medical or scientific papers, posters, and oral presentations. This can cause substantial communication difficulties for individuals who are not familiar with English abbreviations in their field. The example below is meaningless to individuals who are not familiar with the abbreviations used.

For example,

IHC study of CNS tissue from MS subjects demonstrated loss of PLP-expressing OLs.

Many individuals, including native English speakers, do not know the difference between an acronym and an abbreviation. Acronyms and abbreviations are formed by combining the first letter or letters of several words. All acronyms are abbreviations, but not all abbreviations are acronyms. An acronym is a special type of abbreviation that can be pronounced as a single word (it can be said), while all other abbreviations are pronounced letter by letter (you say each letter individually or spell it out).

For example,

AIDS is an acronym for Acquired Immune Deficiency Syndrome because you say the abbreviation as a word (“aydz”); whereas HIV is an abbreviation for Human Immunodeficiency Virus (in this case you say each letter individually).

It can be extremely frustrating and time-consuming trying to find out what certain commonly used acronyms and abbreviations mean. Abbreviations that some consider universally known may be obscure to others. In addition, shortened forms used in one country may not be understood in another. In order to eliminate guesswork and prevent frustration, we have put together an alphabetized list of the most commonly used English acronyms and abbreviations in biomedical research. We feel that having a central reference list at your fingertips could be quite helpful for your scientific communications.

Abbreviation Rules and Style Conventions in English

Apply the following guidelines when using abbreviations:

• On the first occurrence of an abbreviation, spell out the full term, with the abbreviation in brackets. Thereafter the abbreviated form may be used by itself.

  For example,

  Oligodendrocytes (OLs) are the cells responsible for producing a fatty protein called myelin. Each OL can supply myelin for several axons and each axon can be supplied by several OLs.

• Abbreviations may be pluralized by adding an s to the end. Plurals of capitalized abbreviations should have no apostrophe because the apostrophe indicates possession. However, plurals of lowercase abbreviations have an apostrophe.

  Examples:

  PCRs (not PCR’s)

  BACs (not BAC’s)

  Drs. (not Dr’s)

  rbc’s (not rbcs)

  Exception 1: Plurals of some abbreviations, particularly in references, are not formed by merely adding an s.

  Examples:

  p for page and pp for pages (not ps or pgs)

  l for line and ll for lines (not ls)

  c for column and cc for columns (not cs)

  Exception 2: Singular and plural units of measure are abbreviated the same. An s is generally not added to the plurals.

  1 km and 5 km (not 5 kms)

  Exception 3: If the abbreviation contains a period (full stop), form the plural with an apostrophe and an s (’s). This is probably because it looks more awkward without apostrophes:

  For example,

  Ph.D.’s

  M.D.’s

  Exception 4: Plurals of single-letter abbreviations are formed by adding [’s].

  For example,

  X’s

• Abbreviations may be made possessive by adding ’s for singular possessive, and s’ for plural possessive.

  For example,

  EMBO’s homepage

• Articles are usually omitted when acronyms are used, being included only when terms or names are written out in full.

  Example:

  The United Nations International Children’s Emergency Fund is a voluntarily funded agency.

  UNICEF was created on December 11, 1946.

• The choice of an indefinite article (a or an) before letter-by-letter abbreviations depends on the pronunciation of the first letter of the abbreviation, not on the written representation of the first letter. If the abbreviation begins with a consonant sound, use a. If it begins with a vowel sound, use an.

  Examples:

  an mRNA molecule - although “m” is a consonant, we use the an article because the first sound we make is an “em” sound.

  an X-ray - this abbreviation begins with a consonant letter, but sounds like it starts with a vowel. The first sound we make is an “eks” sound.

There are several abbreviation styles used today. The only rule one should remember is to have a consistent style.

• Acronyms are generally presented in uppercase letters.

  Examples:

  AIDS, NATO, BBC, and SARS

  However, some acronyms are no longer capitalized. Examples are laser, radar and sonar.

• A period is sometimes written after an abbreviated word (there is no strict rule). The general modern trend is to omit periods from abbreviations (to avoid an appearance of clutter).

Organizations, countries, and units of measure are not generally followed by periods.

Examples:

EU (not E.U.)

UN (not U.N.)

IBM (not I.B.M.)

5 mg (not 5 mg.)

Periods are optional with degree titles (this is a matter of preference). However, in modern usage, periods are usually omitted.

Examples where both forms are acceptable:

PhD or Ph.D.

BSc or B.Sc.

MD or M.D.

• If a sentence ends with an abbreviation that requires a period, do not add another period.

  For example,

  The technician will be here at 4 p.m.

  not The technician will be here at 4 p.m.

• Abbreviations of chemicals from the periodic table always start with a capital letter; if there is a second letter, it is always lowercase.

  For example,

  N Nitrogen

  O Oxygen

  Na Sodium

  Zn Zinc

• Do not divide abbreviations, or a numerical value followed by a unit of measure, between lines on a page.

  ………………AIDS ………………10 mg

  not……………AI not………………10

  DS mg

Table 1. List of abbreviations and Latin expressions used in scientific writing

General Abbreviations and Acronyms Used in Biomedical Research

A:

Adenine or alanine

aa:

Amino acid or aminoacyl

Ab:

Antibody

ABU:

L-a-Aminobutyric acid

ABZ:

2-Aminobenzoyl

AC:

Accession number

ac:

Acetyl

Ac:

Actinium

Ac-CO A:

Acetyl-coenzyme A

AChE:

Acetylcholinesterase

Acm:

Acetamidomethyl

ADH:

Alcohol dehydrogenase

ADP:

Adenosine diphosphate

AFC:

7-Amino-4-trifloromethyl-coumaride

Ag:

Antigen or silver

Aha:

7-Aminoheptanoic acid

Al:

Aluminum

Ala:

Alanine

Am:

Americium

AMP:

Adenosine monophosphate

Amp:

Ampicillin

an:

Anisoyl

ANOVA:

Analysis of variance

AP:

Anteroposterior or action potential or alkaline phosphatase

APC:

Antigen presenting cells

apoE:

Apolipoprotein E

APP:

Amyloid Precursor Protein

APS:

Ammonium persulfate

Ar:

Argon

Arg:

Arginine

As:

Arsenic

ASA:

Acetyl salicylic acid

Asn:

Asparagine

Asp:

Aspartic acid

At:

Astatine

ATP:

Adenosine 5’- triphosphate

ATPase:

Adenosine triphosphatase

Au:

gold

B:

Boron or bromouridine

Ba:

Barium

BAC:

Bacterial artifi cial chromosome

BAP:

Bacterial alkaline phosphatase

BCIP:

5-Bromo-4-chloro-3-indolyl phosphate

Be:

Beryllium

bh:

Benzhydryl

Bh:

Bohrium

Bi:

Bismuth

Bio-dNTP:

Biotin-deoxynucleoside triphosphate

Bk:

Berkelium

BLAST:

Basic Local Alignment Search Tool

BME:

Beta-mercaptoethanol

BMT:

Bone marrow (or blood and marrow) transplant

Bp:

Base pair

Br:

Bromine

BrUrd:

Bromouridine

BSA:

Bovine serum albumin

bz:

Benzoyl

bzy:

Benzyl

C:

Carbon or cytosine or cysteine

Ca:

Calcium

CA:

Casamino acids

CAT:

Chloramphenicol acetyl

CD:

Central domain

Cd:

Cadmium

cDNA:

Complementary deoxyribonucleic acid

Ce:

Cerium

Cf:

Californium

CFU:

Colony-forming units

CIAP:

Calf intestinal alkaline phosphatase

cl:

Chloro

Cl:

Chlorine

Cm:

Curium

Co:

Cobalt

Cr:

Chromium

Cs:

Cesium

CSF:

Cerebrospinal fluid

CTP:

Cytidine 5’-triphosphate

Cu:

Copper

Cyd:

Cytidine

Cys:

Cysteine

D:

Aspartic acid

dAMP:

Deoxyadenosine monophosphate

dATP:

Deoxyadenosine triphosphate

DAG:

Diacylglycerol

Db:

Dubnium

dCTP:

Deoxycytidine triphosphate

ddATP:

Dideoxycytidine triphosphate

ddCTP:

Dideoxyadenosine triphosphate

ddGTP:

Dideoxyguanosine triphosphate

ddNTP:

Dideoxynucleoside triphosphate

DEAE:

Diethylaminoethyl

DEPC:

Diethyl Pyrocarbonate

dGTP:

Deoxyguanosine triphosphate

DIDS:

4,4’-di-isothiocyanato-2,2’-disulfostilbene

DIG:

Digoxigenin

DIV:

Days In Vitro

DMF:

N,N-Dimethylformamide

DMS:

Dimethylsulfi de

DMSO:

Dimethyl sulfoxide

DMT:

Dimethyltryptamine

DNA:

Deoxyribonucleic acid

DNase:

Deoxyribonuclease

dns:

Dansyl

Dnp:

2,4-Dinitrophenyl

dNTP:

Deoxyribonucleotide triphosphate

DPI:

Diphenylene iodonium

Dpr:

2,3-Diaminopropionic acid

Ds:

Darmstadtium

ds:

Double stranded

DT:

Diphtheria toxin

DTA:

Diphtheria toxin A chain

DTE:

Dithienylethene

DTT:

Dithiothreitol

dTTP:

Deoxythymidine triphosphate

dUTP:

Deoxyuridine triphosphate

DV:

Dorsoventral

Dy:

Dysprosium

E:

Glutamic acid

EDT:

1,2-Ethanedithiol

EDTA:

Ethylenediaminetetraacetic acid

EGTA:

Ethylene glycol tetraacetic acid

ER:

Endoplasmic reticulum

Er:

Erbium

Es:

Einsteinium

EtBr:

Ethidium Bromide

EtOH:

Ethanol

Eu:

Europium

exo:

Exonuclease

F:

Fluorine or phenylalanine

fa:

Formylaminoacyl

FBS:

Fetal bovine serum

FCS:

Fetal calf serum

Fe:

Iron

FITC:

Fluorescein isothiocyanate

Fm:

Fermium

FOA:

5-Fluoroacetic acid

Fr:

Francium

FSH:

Follicle-stimulating hormone

g:

Gram

g:

Gravitational force

G:

Glycine

Ga:

Gallium

Gd:

Gadolinium

Ge:

Germanium

GFP:

Green Fluorescent Protein

Gln:

Glutamine

Glu:

Glutamic acid

Gly:

Glycine

GM:

Genetically Modified

GMO:

Genetically Modified Organisms

GUS:

Beta-D-glucuronidase

H:

Hydrogen or histidine

Hb:

Hemoglobin

HBSS:

Hank’s Buffered Salt Solution

HCl:

Hydrochloric acid

H&E:

Hematoxylin and Eosin

He:

Helium

HEPES:

4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid)

Hf:

Hafnium

Hg:

Mercury

His:

Histidine

HLA:

Histocompatibility Leukocyte Antigen

hm:

Hydroxymethyl

Ho:

Holmium

HPRT:

Hypoxanthine phosphoribosyltransferase

HRP:

Horseradish peroxidase

Hs:

Hassium

Hsp:

Heat Shock Protein

HT:

High temperature

hU:

Dihydrouridine

humi.:

Humidity

Hyl:

Hydroxylysine

Hyp:

Hypoxanthine

I:

Iodine or isoleucine

Ig:

Immunoglobulin

IgA:

Immunoglobulin A (gamma A immunoglobulin)

IgD:

Immunoglobulin D (gamma D immunoglobulin)

IgE:

Immunoglobulin E (gamma E immunoglobulin)

IgG:

Immunoglobulin G (gamma G immunoglobulin)

IgM:

Immunoglobulin M (gamma M immunoglobulin)

IIe:

Isoleucine

In:

Indium

Ino:

Inosine

IPP:

Isopentenyl diphosphate

IPTG:

Isopropyl-beta-D-thiogalactopyranoside

IR:

Infrared

Ir:

Iridium

K:

Potassium or lysine

Kr:

Krypton

L:

Leucine

La:

Lanthanum

LB:

Luria-Bertani medium or Luria broth

Leu:

Leucine

Li:

Lithium

Lr:

Lawrencium

LTA:

Lipoteichoic Acid

Lu:

Lutetium

Lys:

Lysine

M:

Methionine

mAb:

Monoclonal antibodies

MCS:

Multiple cloning site

Md:

Mendelevium

MeOH:

Methanol

Met:

Methionine

Mg:

Magnesium

MgCl:

Magnesium chloride

MMLV:

Moloney murine leukemia virus

mmt:

Monomethoxytrityl

Mn:

Manganese

Mo:

Molybdenum

MOPS:

4-Morpholinepropanesulfonic acid

mRNA:

Messenger Ribonucleic Acid

Mt:

Meitnerium

MTS:

3-(4,5dimethylthiazol--yl)-5-(3- carboxymethozyphenyl-2-(4-sulfophenyl)-2H- tetrazolium

mtDNA:

Mitochondrial DNA

N:

asparagine or nitrogen

Na:

Sodium

NaF:

Sodium fl uoride

NAD:

Nicotinamide adenine dinucleotide

NADH:

Nicotinamide adenine dinucleotide (reduced form)

NADP:

Nicotinamide adenine dinucleotide phosphate

NADPH:

Nicotinamide adenine dinucleotide phosphate (reduced form)

Nb:

Niobium

NBT:

Nitroblue tetrazolium

Nd:

Neodymium

Ne:

Neon

Ni:

Nickel

NMDA:

N-methyl-D-aspartic acid

No:

Nobelium

Np:

Neptunium

nRNA:

Nuclear RNA

NT:

Nucleotides or nuclear transfer or null type

NTP:

Nucleoside triphosphate

NZCYM:

Casein hydrolysate casamino acids yeast extract magnesium medium

O:

Oxygen or orotidine

OD:

Optical Density

Oilgo(dT):

Oligodeoxythymidylic acid

OMP:

Orotidine monophosphate

o/n:

Over night

Ord:

Orotidine

ORF:

Open reading frame

Oro:

Orotate

Os:

Osmium

P:

Phosphorus or praline

Pa:

Protactinium

PAC:

P1 artifi cial chromosome

Pb:

Lead

PBMC:

Peripheral blood mononuclear cells

PBS:

Phosphate Buffer Saline

Pd:

Palladium

PEI:

Polyethylenimine

PEG:

Polyethylene glycol

PFU:

Plaque-forming units

Phe:

Phenylalanine

PK:

Protein kinase

PIPES:

Piperazine-N,N’-bis(2-ethanesulfonic acid)

Pm:

Promethium

PMSF:

Phenylmethylsulfonyl fl uoride

PNK:

Polynucleotide kinase

Po:

Polonium

Poly(A):

Polyadenylic acid

Poly(A)+:

Polyadenylated messenger Ribonucleic Acid

Poly(U):

Polyuridylic acid

Pr:

Praseodymium

Pro:

Proline

Pt:

Platinum

PTX:

Pertussis toxin

Pu:

Plutonium

Puo:

Purine nucleoside

Pur:

Purine

PVC:

Polyvinyl chloride

Pyd:

Pyrimidine nucleoside

Pyr:

Pyrimidine

Q:

Glutamine or ubiquinone (coenzyme Q)

R:

Arginine

Ra:

Radium

Rb:

Rubidium

Re :

Rhenium

Rf:

Rutherfordium

Rg:

Roentgenium

Rh:

Rhodium

Rn:

Radon

RNA:

Ribonucleic acid

RNase:

Ribonuclease

RNP:

Ribonucleoprotein

RRM:

RNA recognition motif

rRNA:

Ribosomal ribonucleic acid

RT:

Room temperature or reverse transcriptase

Ru:

Ruthenium

Rxn:

Reaction

S:

Sulphur or serine

Sb:

Antimony

Sc:

Scandium

SDS:

Sodium Dodecyl Sulfate

Se:

Selenium

Ser:

Serine

Sg:

Seaborgium

Si:

Silicon

Sm:

Samarium

Sn:

Tin

SR:

Sarcoplasmic reticulum

Sr:

Strontium

ss:

Single stranded

SSC:

Sodium citrate buffer

STR:

Short tandem repeats

T:

Threonine

Ta:

Tantalum

TAE:

Tris-acetate buffer

Taq:

Thermus aquatic DNA polymerase

Tb:

Terbium

TBE:

Tris/Borate/EDTA buffer

TBS:

Tris-Buffered Saline

TBST:

Tris-Buffered Saline Tween-20

Tc:

Technetium

TCA:

Trichloroacetic acid

TdT:

Terminal deoxynucleotidyl transferase

Te:

Tellurium

TE:

Tris/EDTA buffer

TEA:

Triethanolamine

TEMED:

N,N,N’,N’-Tetramethylethylenediamine

TES:

N-Tris(hydroxymethyl)methyl-2- minoethanesulfonic acid

Tg:

Transgenic

TGB:

Tris/Glycine buffer

Th:

Thorium

Thr:

Threonine

Ti:

Titanium

Tl:

Thallium

Tm :

Thulium

TP:

Thymidine phosphorylase

TRIS:

Tris-hydroxymethyl-aminomethanel

tRNA:

Transfer RNA

Trp:

Tryptophan

Tyr:

Tyrosine

U:

Uranium or uridine

UP:

Uridine phosphorylase

Ura:

Uracil

Urd:

Uridine

UTP:

Uridine triphosphate

UTR:

Untranslated region

Uub:

Ununbium

Uuh:

Ununhexium

Uun:

Ununnilium

Uuo:

Ununoctium

Uup:

Ununpentium

Uuq:

Ununquadium

Uus:

Ununseptium

Uut:

Ununtrium

Uuu:

Unununium

UV:

Ultraviolet

V:

Vanadium or valine

Val:

Valine

W:

Tungsten or tryptophan

WT:

Wild-type

Xan:

Xanthine

Xe:

Xenon

X-Gal:

5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside

X-Gluc:

5-bromo-4-chloro-3-indolyl-beta-D-glucuronic acid

Y:

Yttrium or tyrosine

YAC:

Yeast Artifi cial Chromosome

Yb:

Ytterbium

YMG:

Yeast and malt extract with glucose media

YPD:

Yeast extract/peptone/dextrose bacterial media

YPG:

Yeast extract/peptone/galactose bacterial media

YT:

Yeast extract/tryptone bacterial media

Zn:

Zinc

Zr:

Zirconium

Please note that amino acids are given three-letter and one-letter abbreviations (e.g. A or Ala for Alanine).

Methods and Techniques Used in Biomedical Research

CHEF:

Contour-clamped homogeneous electric fi eld gel electrophoresis

CSGE:

Conformation-sensitive gel electrophoresis

DFP:

DNA fi nger printing

DGGE:

Denaturing gradient gel electrophoresis

ELISA:

Enzyme-linked immunosorbent assay

EMSA:

Electrophoresis mobility shift assay

ENDO:

Endodeoxyribonuclease assay

EXO:

5’ and 3’ exodeoxyribonuclease assay

FACS:

Fluorescence-activated cell sorting

FIGE:

Field inversion gel electrophoresis

FISH:

Fluorescent in situ hybridization

GC:

Gas chromatography

HPLC:

High performance liquid chromatography

HTRF:

Homogeneous time-resolved fl uorescence assay

IEF:

Isoelectric focusing

IHC:

Immunohistochemistry

IP:

Immunoprecipitation

ISH:

In situ hybridization

LCR:

Ligase chain reaction

MNR:

Nuclear magnetic resonance

MS:

Mass Spec

MZE:

Multiphasic zone electrophoresis

NAAT:

Nucleic acid amplifi cation technique

NB:

Northern blot

PAGE:

Polyacrylamide gel electrophoresis

PCR:

Polymerase chain reaction

PFGE:

Pulsed-fi eld gel electrophoresis

PRINS:

Primed in situ labeling

qPCR:

Quantitative PCR

RDA:

Representational difference analysis

REMI:

Restriction enzyme mediated integration

RFLP:

Restriction fragment length polymorphism

RGE:

Rotating gel electrophoresis

RPA:

Ribonuclease protection assay

SB:

Southern blot

SCGE:

Single cell gel electrophoresis

SDA:

Strand displacement amplifi cation

TAFE:

Transverse alternating-fi eld electrophoresis

TAP:

Tandem affi nity purifi cation

TGGE:

Temperature gradient gel electrophoresis

TLC:

Thin layer chromatography

WB:

Western blot

Radioactive Isotopes

¹⁴C:

Carbon-14

³H:

Tritium-3

¹³¹I:

Iodine-131

³²P:

Phosphorus-32

³³P:

Phosphorus-33

³⁵S:

Sulfate-35

Cell Lines

3T3:

Mouse embryo fibroblast cell line

9L:

Rat glioma

A549:

Human lung cancer cell line

B104:

Rat neuroblastoma

BHK:

Baby hamster kidney cells

B-LCL:

B-lymphoblastoid cell line

C6:

Rat glioma

CHO:

Chinese hamster ovary

CLL:

Carcinoma cell line

CMT:

Canine mammary tumor

COS:

(monkey kidney)

CV-C:

African green monkey kidney cell line

EC:

Embryonal carcinoma (human)

EJ:

Human bladder cancer cell line

GH3:

Rat pituitary tumor cell line

HaCaT:

Human keratinocyte cell line

HEK:

Human embryonic kidney

HeLa:

Henrietta Lacks (human cervical cell line)

HL-60:

Human leukemia cell line

MCF-7:

Human breast cancer cell line

MDCK:

Madin-Darby canine kidney

NS0:

Mouse myeloma cell line

PC12:

Chromaffin cell line (rat)

SCLC:

Small cell lung cancer cell line

SPEV:

Swine kidney cell line

SW480:

Human colon cancer cell line

U87:

Human glioblastoma-astrocytoma cell line

U343:

Human astrocytoma cell line

Units of Measurement

Always abbreviate units when reporting numerical information. However, if you write the number out in full, you must spell out the unit of measurement. Always put a space between the number and the unit. When starting a sentence with a number and unit, both must be spelled out as words. Abbreviations for most units of measurement use small letters. The following abbreviations of units of measurement are frequently used in biomedical research.

A:

Ampere

a:

Area

A₂₆₀ :

Absorbance measured at 260 nm

Bq:

Becquerel

C:

Coulomb

^oC:

Degree Celsius

cal:

Calorie

Ci:

Curie

cm:

Centimeter

cpm:

Counts per minute

d:

Day

Da:

Dalton

DIV:

Days in vitro

dpm:

Disintegrations per minute

F:

Fahrenheit

g, gr:

Gram (g is commonly used)

h:

Hour

Hz:

Hertz

J:

Joule

k:

Kilo (10³)

kb:

Kilobases

kDa:

Kilodalton

L:

Liter

lb:

Pounds

M:

Molar

m:

Meter

mA:

Milliamps

Mb:

Megabase

mg:

Milligram

min:

Minute

mL:

Milliliter

mM:

Millimolar

mmol:

Millimole

mo:

Month

mol:

Mole

ms, msec:

Milliseconds (ms is generally used)

mV:

Millivolt

MW:

Molecular weight

N:

Newton

n:

Nano or sample size

ng:

Nanogram

nm:

Nanometer

OD:

Optical density

oz:

Ounces

pH:

Power of hydrogen

r:

Revolution

rpm:

Revolutions per minute

S:

Svedberg units

s, sec:

Seconds (s is generally used)

T_m :

Melting temperature

U:

Unit

μ:

Micron

μM:

Micromolar

μm:

Micrometer

w, W:

Watt (W is commonly used)

wk:

Week

wt:

Weight

w/v:

Weight to volume

y:

Year

V_max :

Maximum velocity

v/v:

Volume to volume