Human Molecular Genetics Human DNA Analysis Human DNA

Human Molecular Genetics

Human DNA Analysis • Human DNA has ~6 billion base pairs. • Impossible to know everything bases contain. • Search through DNA using sequences of DNA bases.

Testing for Alleles • Use labeled DNA probes – Specific DNA base sequences that detect the complementary base sequences found in disease-causing alleles • Changes in restriction enzymes cutting sites • Differences between the lengths of normal and abnormal alleles

Genetic Tests • Possible to determine whether prospective parents risk passing abnormal alleles to their offspring • Pinpoint the exact genetic basis of a disorder • Develop more effective treatment for individuals with genetic disorders

DNA Fingerprinting • Analyze sections of DNA that have little or no known function but vary widely form one individual to another. • Used to identify individuals. HOW? – Cut small DNA sample with restriction enzyme. – Separate the fragments with gel electrophoresis. – Use a DNA probe to detect fragments with highly variable regions.

DNA Fingerprint

DNA Finger Print

Human Genome Project • Began in 1990 with scientists in the U. S. and other countries. • Analyze the human DNA sequence. • Completed the genome for yeast & a fruit fly. • In 2000, a working copy of the human genome was completed.

Human Genome Project

Gene Therapy • Process of changing the gene that causes a genetic disorder. • An absent or faulty gene is replaced by a normal working gene. • Unsure of how long the benefits will last.