1. BDdb is the first comprehensive database associated with birth-defect-related diseases. which would benefit the diagnosis and prevention of birth defects.

2. BDdb is consisting of multi-omics datasets involving tens of common birth-defect diseases, and BDdb supplements more than 2000 biomarkers belonging to 22 types of birth defects.

3. The easy-to-use interface provides access for searching, browsing, visualizing and downloading.

Birth defects have been being in the limelight due to posing a major challenge for infant health. Genetic factors, especially chromosome abnormality, play an important role in their occurrence. Over the past decades, considerable efforts have been put on understanding the underlying mechanism of birth defects-related diseases, resulting in a myriad of treatises and data. To meet the increasing requirements for birth-related data resources, we developed a birth defect multi-omics database (BDdb), freely accessible at http://t21omics.cngb.org and consisting of multi-omics data as well as potential diseases biomarkers. Omics data sets from 138 GSE samples, 5271 GSM samples, 328 entries, and more than 2000 biomarkers of 22 birth defects-related diseases in 6 different species were integrated into BDdb, which provides a user-friendly interface for searching, browsing and downloading data of interest. Additionally, BDdb enables users to mine the correlation between different sequencing methods such as ChIP-Seq and RNA-Seq from different studies, to get the information of a gene from diverse aspects. To our knowledge, BDdb is the first comprehensive database associated with birth defects-related diseases, which would benefit the diagnosis and prevention of birth defects.