440 likes | 582 Views
Anno accademico 2002-2003 Canale A: Prof. Malavasi. Lezione 1: La Genetica Umana sul web Il Progetto Genoma Umano. http://www.ncbi.nlm.nih.gov/omim/. - OMIM: online mendelian inheritance in man - Creato da Victor McKusick - Continuamente aggiornato
E N D
Anno accademico 2002-2003 Canale A: Prof. Malavasi Lezione 1: La Genetica Umana sul webIl Progetto Genoma Umano
http://www.ncbi.nlm.nih.gov/omim/ - OMIM: online mendelian inheritance in man - Creato da Victor McKusick - Continuamente aggiornato - Punto chiave per acquisire informazione sui caratteri mendeliani umani, patologici e non - A ogni carattere viene attribuito un numero a 6 cifre MIM
Human Genome Project • 1970: possibilità di manipolare il DNA • 1980: costruzione di parti della Human Genome Map • 1988: inizio della collaborazione scientifica internazionale attraverso HUGO • 1990: programmi di ricerca sul genoma iniziati in Italia, Inghilterra, Francia, Europa, Giappone e Canada • 1990: l’NIH e il US Dept of Energy hanno dato il via a un progetto congiunto di 5 anni • prerequisiti:
Bilancio del Progetto Genoma Umano Studi sull’uomo Costi di funzionamento Altri organismi
The labeled probe DNA or RNA are separated on a gel The gel is transfered to a filter finds complementary targets Hybridization of nucleic acids is based on complementarity A DNA or RNA “probe” is a single strand nucleid acid whose nucleotide sequence allows it to hybridize uniquely to its complementary nucleic acid In classical techniques such as Southern or Northern blotting
Hybridization to solid-state probe array allows detection of multiple sequences in the same complex sample Individual probes are spotted to a filter RNA or DNA are extracted from tissues … labeled during RT …and hybridized to the filter
DNA chips: thee are currently two major types available: 10,000 - 20,000 probes / cm2 are spotted on glass slides using an automated microarrayer Probes are cDNA or PCR products representing known genes or simply EST cDNA microarrays Up to 250,000 oligonucleotides / cm2 are sythesized directly on the chip surface, using a photolitographic technique. These 20-25nt long oligonucleotides represent sequences of known genes or EST Oligonucleotide arrays
Dot diameter: 200m Pitch: 400 m Highly parallel probe arrays: “DNA chips”
Fluorochrome labelling of DNA and RNA RNA from sample and from reference are labeled by introducing two different fluorochromes. This allows co-hybridization of the two samples to the same chip, providing direct comparison by two-color analysis
Use of microarrays for Gene Expression Profiling “Test” sample (tumor tissue, stimulated cells) RNA Extraction, cDNA Synthesis and labelling Hybridization “reference” sample (normal tissue, unstimulated cells)
HNF3a KDR/Flk1 ERa Keratin 17 ->6-fold -3-6-fold -1-3-fold equal to median +1-3-fold +3-6-fold +>6-fold Troponin I Integrin b4 GATA bp3 AP-2a ……. …… ….. …. ... Laser scanning of individual chips Gene Id. Sample X Transformation to false-color code Representation of results
->6-fold -3-6-fold -1-3-fold equal to median +1-3-fold +3-6-fold +>6-fold Cluster analysis 1 HMEC HUVEC MDAMB231 BT549 SKBR3 BT474 MCF7 T47D HNF3a KDR/Flk1 ERa Keratin 17 Troponin I Integrin b4 GATA bp3 AP-2a
->6-fold -3-6-fold -1-3-fold equal to median +1-3-fold +3-6-fold +>6-fold Cluster analysis 2 HMEC HUVEC MDAMB231 BT549 SKBR3 BT474 MCF7 T47D KDR/Flk1 AP-2a Troponin I Keratin 17 Integrin b4 HNF3a GATA bp3 ERa