(Apr 20, 2026): A sum of 7,562 new QTL/associations have been curated into the database. (New additions less obsolete/retracted ones: Cattle: 5,291; Chicken: 1,137; Goat: 322; Horse: 0; Pig: 173; Sheep: 639; Rainbow trout: 0 -- Net increase: 7,562). To date, the current total number of QTL in the database: 318,441 [Breakdown by species -- Cattle: 212,372 (on 572 traits); Chicken: 30,465 (on 244 traits); Goat: 3,115 (on 92 traits); Horse: 2,545 (on 71 traits); Pig: 58,517 (on 410 traits); Sheep: 9,226 (on 191 traits); Rainbow trout: 2,201 (on 35 traits)] curated from 3,038 publications.

In addition, data updates were made to about 1,097 QTL/associations, 67 base traits, and 39 trait variants, partly as a result of active developments of trait ontologies (VT, LPT, CMO). Base trait updates by species -- cattle: 17; chicken: 18; goat: 4; pig: 173; horse: 3; pig: 15; sheep: 10.

Database developments notes:

(1) With ongoing improvements in genome assemblies and SNP mappings, the relevance of several older genome builds has declined, particularly in terms of their use for lifting QTL and association data. As a result, four genome builds — Btau4 (cattle), GG4 (chicken), SS10 (pig), and OAR3 (sheep) — have been retired from the QTLdb supported genome list.

It is important to note that this change only affects their availability for QTL/association data lifting and downloads. Curation of data originally reported using these genome builds will continue, and such data will be lifted to the default genome in future QTLdb releases.

(2) Webtools improvements were continued and a number of bug fixes were made since the last release.

For most recent updates, please refer to What's New page on this site for related items.