Mrs. Stewart Honors Biology Central Magnet School

 Except for identical twins, no two people in the world are genetically alike. .10 percent of everyone’s DNA is different  Scientists can identify you based on that.10 percent difference

 Non-coding regions of DNA have “repeating segments of nucleotides” called Variable number tandem repeats.  The number of repeats and the location of the repeats differs among individuals.  13 of these loci are compared to produce a DNA Fingerprint.  Odds of 2 people sharing 13 different loci are about 1 in 100 billion.

 Polymerase Chain Reaction  This technology quickly produces many copies of a DNA fragment  Requires a template, a supply of extra nucleotides, DNA polymerase and primers  Primer – single strand of a specific DNA sequence

 Enzymes that recognize specific DNA base sequences and “cut” the DNA  Makes a “zig zag” cut to leave a “sticky end”  Sticky ends allow the DNA to reanneal (rebind).

 DNA fragments that have been amplified (multiplied in number) through PCR can be run through a gel that separates the fragments according to size.  An electric current is applied to the gel, causing the negatively charged phosphate groups of the DNA to migrate toward the positive pole.

 DNA is collected and run through PCR  Amplified DNA is cut with restriction enzymes  DNA is loaded into the gel and electric current is applied  DNA travels toward positive pole in the gel  Smallest fragments will move farthest down the gel  Gel Electrophoresis virtual lab Gel Electrophoresis virtual lab

 Joining the DNA from two different organisms.  Genetic engineering – the process of altering the genetic material of cells to allow them to make new substances.  Vectors carry the DNA and insert it into the host cell.

 Treatment of a genetic disorder by introducing a gene into patient’s cells  Work best for disorders caused by the loss/malfunction of a single protein.  Not yet a viable option

 Paternity testing  Identify criminals  Free the wrongly convicted  Trace human origins and migrations  Trace migrations and movements of threatened/endangered species  Produce medically important proteins:  insulin, clotting factors, HGH

 The research effort taken to sequence all of our DNA and locate within it all of the functionally important sequences, such as genes.  Important insights:  Only about 2 percent of the human genome codes for proteins  Chromosomes have an unequal distribution of exons (coding regions of DNA)  Genome is smaller than believed. Only about ,000 protein coding genes.

 Scientists have discovered many of the genes responsible for genetic disorders, such as:  Cystic fibrosis  Duchenne muscular dystrophy  Colon cancer  These discoveries have improved diagnostic techniques, treatments and therapies.

 Uses the nucleus of a somatic cell and impants it into an unfertilized egg cell (that has had it’s nucleus removed)  This egg cell is then implanted in a surrogate for growth as an embryo into a complete organism.

 Taking the nucleus from a somatic cell and placing it into an anucleated egg cell  Grown as an embryo until reaches the “stem cell” stage  Engineered to grow as desired cells only – producing new organs, cells, etc.

 Genetically modified crops – plants created by genetic engineering  More tolerant to environmental conditions  Can improve the “nutritional” value  Can make plants resistant to certain plant diseases

 Study of ethical issues related to DNA technology