Articles include a competing financial interests statement and received/accepted dates. They may be accompanied by supplementary information. Articles are peer reviewed.

A Letter reports an important novel research result, but is less substantial than an Article. This format begins with an introductory paragraph (not abstract) of approximately 150 words, summarizing the background, rationale, main results and implications. This paragraph should be referenced, as in Nature style, and should be considered part of main text, so that any subsequent introductory material avoids too much redundancy with the introductory paragraph. The text is limited to 1,200 words, excluding the introductory paragraph, Methods, references and figure legends. References are limited to 30. Letters should have no more than 6 display items (figures/tables). Letters are not divided by headings, except for the Methods heading.

Letters include a competing financial interests statement and received/accepted dates. They may be accompanied by supplementary information. Letters are peer reviewed.

A Technical Report presents primary research data on a new technique that is likely to be influential. This format is not a review of technology, but its primary report in the literature. It may involve a new biological discovery to prove the usefulness of the technique, but this is not a requirement. Technical Reports have a format broadly similar to that of Articles, though many Technical Reports are shorter than a typical Article. They begin with an unreferenced abstract (typically 150 words) followed by separate sections for introduction, Results, Discussion (with optional subheadings) and Methods. There is no strict limit on the number of display items (figures/tables). References are normally limited to 30, but this can be flexible at the editor’s discretion.

Technical Reports include a competing financial interests statement and received/accepted dates. They may be accompanied by supplementary information. Technical Reports are peer reviewed.

A Brief Communication reports a study of high quality and broad interest that is less fully developed than a Letter or Article. This format may not exceed 2 printed pages. Brief Communications begin with a brief unreferenced abstract (no more than 70 words or 3 sentences), which will appear on Medline. The main text is typically 1,000?,500 words, including abstract, references and figure legends, and contains no headings. Brief Communications normally have no more than 2 display items (figures/tables), although this may be flexible at the discretion of the editor, provided the page limit is observed. References are limited to 15. Article titles are omitted from the reference list.

Brief Communications include a competing financial interests statement and received/accepted dates. They may be accompanied by supplementary information. Brief Communications are peer reviewed.

Other formats

 
Correspondence (formerly Letters to the Editor) is a flexible format that may include anything of interest to the journal’s readers, from policy debates to announcements to ‘matters arising?from research papers. A Correspondence may describe primary research data, but only in summary form; this format is not intended for full presentation of data. Correspondence should never be more than one printed page, and usually much less. References from a Correspondence and its Reply are combined into a single list, numbered in order of appearance and placed at the end of the Reply. The number of references should not exceed 10 for either the Correspondence or its Reply. Titles are supplied by the editors.

Correspondence is the only section of the journal that may include replies from people whose views or findings are being criticized. Authors whose primary research data are being criticized should normally have the right of public reply. Criticism of opinions or other secondary matter do not involve an automatic right of reply.

Except for refutations, Correspondence is not normally peer reviewed (although it may be at the editors?discretion).

A Review is an authoritative, balanced and scholarly survey of recent developments in a research field. The requirement for balance need not prevent authors from proposing a specific viewpoint, but if there are controversies in the field, the authors must treat them in an even-handed way. Reviews are normally 3,000?,000 words, and illustrations are strongly encouraged. References are limited to 100, with exceptions possible in special cases. Citations should be selective. The scope of a Review should be broad enough that it is not dominated by the work of a single laboratory, and particularly not by the authors?own work.

A competing financial interests statement is optional, at the authors?discretion. Received/accepted dates are not included. Reviews are always peer reviewed to ensure factual accuracy, appropriate citations and scholarly balance.

Commentary is a very flexible format; Commentaries may be on policy, science and society or purely scientific issues. The main criteria are that they should be of immediate interest to a broad readership and should be written in an accessible, non-technical style. In contrast to a Review, publication as a Commentary does not imply editorial endorsement of the authors?opinions. Their length is typically 1? pages, although some may be longer. Because the content is variable, the format is also flexible. Commentaries do not contain primary research data, although they may present ‘sociological?data (funding trends, demographics, bibliographic data, etc.). References are limited to 25, and article titles are omitted from the reference list.

The related format Historical Commentary is a journalistic treatment of the history of a particular discovery or technical development. These pieces may be a personal account by one of the participants or may present strong personal opinions. This format does not necessarily seek scholarly balance, and it should be journalistic and accessible rather than scholarly in style.

A competing financial interests statement is optional, at the authors?discretion, although authors are encouraged to indicate their affiliations. Commentaries may be peer reviewed at the editors?discretion.

Perspective is a new format for scholarly reviews and discussions of the primary research literature that are too technical for a Commentary but do not meet the criteria for a Review—either because the scope is too narrow, or because the author is advocating a controversial position or a speculative hypothesis or discussing his/her own work. Two reviews advocating opposite sides in a research controversy are normally published as Perspectives. The text should not normally exceed 3000 words. References are limited to 50.

The related format Historical Perspective is a more technical account of a particular scientific development. Like other Perspectives, and in contrast to Historical Commentary, Historical Perspectives are scholarly reviews, including citation of key references, aiming to present a balanced account of the historical events, not merely personal opinions or reminiscences.

Heading:
As concise and informative as possible. Authors' affiliations are depicted with numerical superscripts. Please give authors' first names.
 
Main Text:
The total length of the main text (excluding figure legends and Methods) must be no more than 1,200 words. In place of the abstract, there should be a single paragraph of introductory material (no more than 200 words) with references, culminating in a brief summary of the results. The remainder of the text should be devoted to presenting the data and principal conclusions of the work. The discussion should be limited to a single, terse paragraph. There are no cross-headings.
 
Genes and loci should be denoted in italics. If referring to the protein product, however, use upright (Roman) text. References should be cited as superscripts (before punctuation), not in parentheses -- unless the reference follows a number, in which case parentheses should be used to avoid confusion. For example, 'chromosome 2 (refs 4?)'. Multiple consecutive references are indicated with a dash.
 
Methods:
A concise description of methods (each starting with a short title) should be presented in a separate section entitled 'Methods'. Previously described methods should be cited without further description.
 
References:
There should be no more than 30 references with titles.

1. There should be one tab after the reference number and period.
2. List author names with last name first. Six or more authors for one paper should be cited as first author followed by et al.
3. No comma before or after et al. in any context. No comma before or after an ampersand (&).
4. Include title of paper.
5. Name of publication in italics.
6. Volume number (bold) followed by comma.
7. Page number range.
8. Year of publication in parentheses.
9. Reference MUST be at least 'in the press' to be in the ref. list (otherwise, cite in text as 'unpublished data').
10. Journal abbreviations are as in Index Medicus/Pub Med.

Figures & Tables:
A maximum of six display items (tables and figures) is allowed. List figures as Fig. 1a, Fig. 2b et cetera. Do not capitalize or embolden heading. Figure panels are designated by lower-case bold text. Tables should have a brief title. There should be only ONE tab between each variable. Do not use any spaces to separate columns.
 
Proofs:
Within a few weeks of acceptance of your final manuscript, you will receive galley proofs for approval. The editor may have suggested certain areas that warrant updating or revising on the proofs; these can be accommodated with ease in the main text (and there is no charge for such corrections) although we do not encourage extensive rewriting. As editorial changes will have been made to ensure clarity and style, proofs should be examined very carefully. Corrected proofs should be faxed back to the Production Editor as soon as possible.