Quick Guide to Gene Nomenclature


The complete guidelines,for gene, variant, and allele nomenclature can be found at http://rgd.mcw.edu/nomen_rules.html


A gene symbol should:

·        be unique within the species and should not match a symbol in another species that is not a homolog,

·        use the same symbol whenever possible for orthologs among human, mouse and rat,

·        be short, normally 3-5 characters, and not more than 10 characters,

·        use only Roman letters and Arabic numbers,

·        begin with an uppercase letter (not a number), followed by all lowercase letters / numbers (see exception below),

·        not include tissue specificity or molecular weight designations,

·        not include punctuation except for hyphens to separate related sequence (rs) and pseudogene (ps) from the root symbol,

·        ideally have the same initial letter as the initial letter of its gene name,

·        use a common stem or root symbol when belonging to a gene family; family member numbers or subunit designations should be placed at the end of the gene symbol,

·        be italicized in published articles although, because they may be difficult to read, depending on the browser, gene symbols are frequently not italicized when posted to a web page.


A gene name should:

·        be specific and brief, conveying the character or function of the gene,

·        begin with a lowercase letter, unless it is a person’s name or is a typically capitalized word,

·        use American spelling,

·        not contain punctuation, except where necessary to separate the main part of the name from modifiers,

·        include the name of the species from which the ortholog/homolog name was derived at the end of the name in parentheses only when that name is not in common usage,

·        not include the word rat,

·        follow the conventions of the established gene family if it is a recognizable member of that family by sequence comparison, structure (motifs/domains), and/or function,

·        not contain potentially misleading information that may be experiment or assay specific, such as “kidney-specific” or “59 kDa”.


A splice variant from a single locus should:


·        be differentiated by the addition of an underscore v and a serial number (_v#) to the symbol and the addition of a comma “variant” and serial number to the name.