title: iHMS: a database integrating human histone modification data across developmental stages and tissues.
abstract: BACKGROUND
  Differences in chromatin states are critical to the multiplicity of cell states. Recently genome-wide histone modification maps of diverse human developmental stages and tissues have been charted.
  
  
  METHODS
  To facilitate the investigation of epigenetic dynamics and regulatory mechanisms in cellular differentiation processes, we developed iHMS, an integrated human histone modification database that incorporates massive histone modification maps spanning different developmental stages, lineages and tissues ( http://www.tongjidmb.com/human/index.html ). It also includes genome-wide expression data of different conditions, reference gene annotations, GC content and CpG island information. By providing an intuitive and user-friendly query interface, iHMS enables comprehensive query and comparative analysis based on gene names, genomic region locations, histone modification marks and cell types. Moreover, it offers an efficient browser that allows users to visualize and compare multiple genome-wide histone modification maps and related expression profiles across different developmental stages and tissues.
  
  
  CONCLUSIONS
  iHMS is of great helpfulness to understand how global histone modification state transitions impact cellular phenotypes across different developmental stages and tissues in the human genome. This extensive catalog of histone modification states thus presents an important resource for epigenetic and developmental studies.
authors.affiliation: School of Computer Science and Technology, Donghua University, Shanghai, China.
authors.forename: Yanglan
authors.initials: Y
authors.lastname: Gan
authors.affiliation: Department of Computer Science and Technology, Tongji University, Shanghai, China.
authors.forename: Han
authors.initials: H
authors.lastname: Tao
authors.affiliation: Department of Computer Science and Technology, Tongji University, Shanghai, China. jhguan@tongji.edu.cn.
authors.forename: Jihong
authors.initials: J
authors.lastname: Guan
authors.affiliation: Shanghai Key Lab of Intelligent Information Processing and School of Computer Science, Fudan University, Shanghai, China.
authors.forename: Shuigeng
authors.initials: S
authors.lastname: Zhou
mesh_terms: D002843:Chromatin / Q000378:metabolism; D018899:CpG Islands; D030541:Databases, Genetic; D006657:Histones / Q000378:metabolism*; D006801:Humans; D020407:Internet; D011499:Protein Processing, Post-Translational; D014584:User-Computer Interface
chemical_list: D002843:Chromatin; D006657:Histones
keywords: Data integration; Database; Developmental stages; Human histone modification