Allergen Online Home of the FARRP Allergen Protein Database
AllergenOnline provides access to a peer reviewed allergen list and sequence searchable database intended for the identification of proteins that may present a potential risk of allergenic cross-reactivity.
This website was designed to help in assessing the safety of proteins that may be introduced into foods through genetic engineering or through food processing methods. The objective is to identify proteins that may require additional tests, such as serum IgE binding, basophil histamine release or in vivo challenge to evaluate potential cross-reactivity.
The database is updated annually. Version 4 was released on a public website in 2004. Version 19 was released on 10 February 2019. The database is freely accessible with the intent of providing a simple and useful tool that may be useful in food safety evaluations.
Features and Tools Available
Sequence search routines for food safety
We continue provide simple amino acid search routines to allow you to compare a protein sequence with the sequences in the current AllergenOnline database, which is updated on an annual basis. This is intended primarily for evaluating new proteins in Genetically Modified crops or in Novel Foods.
Search for full-length alignments by FASTA: The most predictive search is the overall FASTA alignment (see FASTA Help Page), with identity matches greater than 50% indicating possible cross-reactivity (Aalberse, 2000).
Search for 80 amino acid alignments by FASTA: A precautionary search using a sliding window of 80 amino acid segments of each protein to find identities greater than 35% (according to CODEX Alimentarius guidelines, 2003).
Search for 8 amino acid exact match: An 8-amino acid short-sequence identity search is provided since some regulatory authorities demand results of this extremely precautionary search. Our scientific opinion is that there is no evidence that an 8 amino acid match will identify a protein that is likely to be cross-reactive and could be missed by the conservative 80 amino acid match (35%). In our experience, isolated identity matches of 8 contiguous amino acids occur by chance alone at some modest rate, matches of 7 and 6 occur more commonly. Experience (published and unpublished) demonstrates that two proteins sharing only a single short identity match of from 6 to 8 contiguous amino acids do not share IgE binding in the absence of more extensive identity alignments (at least >35% identity over 80 or more amino acids). And that sequences sharing less than 50% identity over their full-lengths are rarely cross-reactive. Thus we recommend not using these short identity matches as there is no scientific evidence that they predict IgE cross-reactivity and they do not predict shared clinical activities.
New Celiac Disease Protein Database Risk Assessment Tool
In 2012 FARRP added a new bioinformatics tool in response to the CODEX Alimentarius Guidelines approved in 2003, to compare query sequences to peptides and proteins known to elicit celiac disease in some people. It was updated to version 2 in January, 2018 and now includes 1013 peptides, 72 proteins and 72 references. This tool meets the new European Food Safety Authority guideline for evaluating proteins from wheat and wheat-relatives for risks of celiac disease (June, 2017). A manusript has been submitted for publication describing the methods, the comparisons that include identity matches to peptides, or high scoring FASTA3 alignments to any of the 72 proteins. The database provides an exact peptide query and FASTA3 search algorithms to evaluate whether a novel protein derived from wheat. See Celiac-Disease for explanation and access to the database.
Who We Are
Allergen Online Team
This database was developed and is maintained by the Food Allergy Research and Resource Program (FARRP) in the Department of Food Science and Technology at the University of Nebraska in Lincoln. John Wise wrote the code and maintained the database through version 14. Sreedevi Lalithambika joined the database in 2014 to 2016 to maintain the system and to help identify new candidate allergens. Richard Goodman manages the database and leads the peer review team.
The content of the AllergenOnline.org database is the sole responsibility of researchers at the University of Nebraska-Lincoln, with the advice and collaboration of additional independent academic and medical consultants. This work is or was co-sponsored by the aforementioned corporate subscribers and the Food Allergy Research and Resource Program at the University of Nebraska-Lincoln. Corporate subscribers had the right to provide scientific input as suggestions. However, all decisions regarding content are the responsibility of the FARRP expert panel. The subscribers and the University of Nebraska, make no representations or warranties of any kind, express or implied, concerning the content of the database, including, without limitation, warranties of merchantability, fitness for a particular purpose, non-infringement, validity of any intellectual property rights or claims, whether issued or pending, and the absence of latent or other defects, whether or not discoverable.