Biological Data Centres

Today, biologists have at their disposal a rich collectionof molecular data in the form of deoxyribonucleicacid (DNA) sequences. Recently, the human genomeinitiative has captured the attention and imaginationof the public, but the large-scale sequencing of genomeshas been quietly underway for decades. The ﬁrst genewas sequenced in 1976 and scientists have been addingto the collection of DNA sequence ever since. From thatﬁrst nucleotide, literally billions more sequenced baseshave been stored in computers and made accessiblethroughon-line biological databases. In 1980theNucleo-tide Sequence Data Library was established at theEuropean Molecular Biological Laboratories (EMBL) inHeidelberg, Germany, and became the ﬁrst public DNAsequence database. The biological database in its manyforms has become an indispensable tool for biologicalresearch. Today research in molecular and cell biologyoften requires some foray into nucleotide or proteindatabases.Although DNA sequence information is simplythe arrangement of four nucleotides that code fora chain of amino acids, the DNA sequence data foran entire organism become incredibly complex andunwieldy. Even after all the human chromosomes havebeensequenced,annotatedandcatalogued,thereremainsthe daunting task of analysing these data so thatthey are made useful. As independent research andcommercial genome sequencing proteins continue toaddtothewealthofinformationwealreadyhave(sequencedata entering the public databases have a doubling timeof approximately 10months), there will be a need toanalyse the data already on hand. It is the responsibilityof biological datacentres toprovide a way toaccess thesedata so that researchers can quickly scan genomes forrelevant information.DNAsequencedatathemselvesareoflimitedutility;onemust be able to place those data in the context of otherinformationinordertoextractpatternsfoundinthedata,andtodocomparisonswithotherorganisms.Thisprocessis know as bioinformatics, a new scientiﬁc ﬁeld thatcombines molecular biology and biochemistry withcomputational approaches to cataloguing and analysinglarge amounts of sequence data. The ultimate goal of thisnew ﬁeld is to enable the discovery of new biologicalinsights from existing data. There are three importantsubdisciplineswithinbioinformatics:. development of computational formulae with which toassess genetic relationships among large numbers oforganisms. analysisandinterpretationofvarioustypesofbiologicaldata including nucleotide and amino acid sequences,protein domainsandproteinstructures. development and implementation of software thatenables access and management of diﬀerent types ofinformationviathe public domain.A specialized type of bioinformatics is known as ‘datamining’. This is the process by which informationconcerningthefunctionofageneisobtainedbyidentifyingsimilarsequencesinbetter-characterizedorganisms.Oftenscientistsare ableto‘mine’informationaboutrelatednessor evolutionary divergence from databases by searchingfor sequence similarities across species. New insight intothemolecularbasisofdiseasemaycomefrominvestigatingthe function of homologues of the disease gene in modelorganisms.Equallyexcitingisthepotentialforuncoveringphylogenetic relationships and evolutionary patterns.Early databases were ill equipped to handle the demandsof such specialized searches and much of today’s datamining would have been impossible. As sequencescontinue to pour in, and more and more species aresequenced,theroleofthebiologicaldatacentrewillplayanincreasingly important and dynamic role in biologyresearch.Three main DNA sequence databases exist as aninternational consortium, the DDBJ (DNA Data Bankof Japan), the EBI (European Bioinformatics Institute)and the NCBI (National Centre for BiotechnologyInformation).