Query Tips

HomoloGene is integrated into Entrez. This means that many features of Entrez search engine such advanced search options like Limits, Index/Preview and History apply to the HomoloGene search engine as well. Look at Entrez Search Help for more information.

To get started with using HomoloGene use search tips below.

Query Type	Explantion	Example
Default search and automatic "AND" queries	Search terms typed in the query box are automatically ANDed i. e. the search engine returns documents that include all of them. Note: Search is not case-sensitive: "PFK1 PFK2" and "pfk1 pfk2" are treated as the same search.	pfk1 pfk2
Including words or boolean "AND" queries	Type AND in front of words that you want to be included in returned documents. Note: All boolean operators (AND, OR and NOT) should be capitalized.	pfk AND mus AND liver
Excluding words or boolean "NOT" queries.	Type NOT in front of words that you want to exlude from your query	pfk NOT mus
Either/Or or boolean "OR" queries	If you equally interested in two or more alternatives, use OR operator.	pfkp OR pfkm
Phrase search	Words enclosed in double quotes appear together in all returned documents.	"cell cycle arrest"
Word variation (wild card search)	To look for entries that contain words with the same prefix append the word's part with trailing wildcard * character.	pfk* tnf*
Search by fields	To search for entries that contain your search term in a particular field you can enter the term followed by the field qualifier in square brackets [ ] in the query box. Hint: To get a list of fields look in dropdown menu on Preview/Index page under Add Term(s) section.	tnf[Text Word] cyclin[Gene Name] arabidopsis[Organism] Bt.12756[UniGene ID]
Complex queries	Combine all of the above tips to construct a complex query	mus[Organism] AND hsd[Gene Name] mus[Organism] AND (hsd[Gene Name] NOT hsd3b2[Gene Name])

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