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The Human Genome Project: Impact on Human Health. Pragna Patel, Ph.D. Institute for Genetic Medicine University of Southern California. Variation in DNA sequence can be “silent” or lead to disease. DNA Genetic Code dictates amino acid identity in a protein.
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The Human Genome Project: Impact on Human Health Pragna Patel, Ph.D.Institute for Genetic MedicineUniversity of Southern California
Variation in DNA sequence can be “silent” or lead to disease
Variation in DNA sequence in gene can change the protein produced by the Genetic Code
Types of Inherited Human Diseases • Single gene disorders – rare, familial (Eg. Hemophilia) • Chromosomal abnormalities – typically sporadic (Eg. Down’s syndrome) • Multifactorial disorders (Eg. Arthritis, diabetes) -Several genes involved, complex inheritance • - Environmental factors
Genome Chromosome AtcgtacgtaggtcagtttaccggtaccatgtataggtacccgggtaccctaccccggcaccTAgcatcatataggacacatactgatcatgcattacggatcgtacgtaggtcagtttaccggtaccatgtataggtacccgggtaccctacccgggga Normal atcgtacgtaggtcagtttaccggtaccatgtataggtacccgggtaccctaccccggcaccAagcatcatataggacacatactgatcatgcattacggatcgtacgtaggtcagtttaccggaccatgtataggtacccgggtaccctacccaggga Patient Gene Challenge of discovering a mutation in the genome
Goals of the Human Genome Project (1990) • Identify all the genes in human DNA (now estimated at ~25,000) • Determine the sequence of 3 billion chemical base pairs that make up human DNA • Determine the sequence of model organisms for comparison to human DNA sequence
Goals of the Human Genome Project (1990) • Store the information in databases • Improve tools for data analysis • Transfer related technologies to the private sector • Address the ethical, legal, and social issues (ELSI) that may arise from the project
The Human Genome Project: Why? Sequence Genome Genetic Mapping, Mutation Detection Find Genes Establish Function and Disease Mechanism Diagnostics/ Prognostics Cure Drug Candidates Gene Therapy
Requisites for genetic mapping of a disease to a chromosome 1. Families with the disease 2. Accurate diagnosis 3. Defined pattern of inheritance 4. Polymorphic DNA markers
Linkage I. 1 2 A a A A N N N D B B b B II. 1 2 3 4 5 6 A A A a A A a A A A A a N N N N N N D N D N N D B b B b B B B B B B B b Tracking a disease mutation-bearing chromosome in a family
1-5 Million base pairs Human genome sequence …..CGACCGGTATGCGATGACTGGTCATGTACTTACTATTC…. Gene content map Gene .......C C T A C......... Normal DNA sequence .......C T T A C......... Patient FINE MAPPING AND MUTATION IDENTIFICATION Post-genome era
2008 Cumulative Pace of Monogenic Disease Gene Discovery: 1981 - 2008 PCR Draft sequence HGP
Current Status of DNA testing for single gene disorders • Directory of International Testing Laboratories • www.genetests.org • 575 Clinical and research laboratories • 1115 Inherited diseases