Announcements

● Tutoring CenterSCI I, 407M 12-3, 5:30-6:30; W 8-9, 5:30-6:30, Th 8-12, 6-7; F 8-9

● MasteringBiology Assignment due Tuesday 5/24●Today’s Lecture: parts of Chapters 11-12

Biotechnology

Biotechnology:Is the manipulation of organisms or their components to make useful products

Biotechnology today means the use of DNA technology, methods for:

•Studying and manipulating genetic material•Modifying specific genes •Moving genes between organisms

BiotechnologyClone – from the Greek “Klon” meaning genetic duplicate

•Reproductive cloning

•Therapeutic cloning

•Recombinant DNA Technology (or DNA cloning)

Reproductive cloning

BiotechnologyReproductive cloning

Reproductive cloningBiotechnologyReproductive cloning

Reproductive Cloning

(a) The first cloned cat (b) Cloning for medical use

Gray wolfGaurBantengMouflon calfwith mother

Human Cloning–Cloning of animals

●Has heightened speculation about human cloning ●Is very difficult and inefficient

–Critics raise practical and ethical objections to human cloning.

Concept Check: Clicker Question•Nuclear transplantation experiments provide strong evidence for which of the following?

A. Differentiated vertebrate cells still maintain their full complement of DNA.B. Differentiated vertebrate cells do not maintain their full complement of DNA. C. Vertebrate cloning is not feasible.D. Cell differentiation is an irreversible process.

Biotechnology–The purpose of therapeutic cloning is not to produce a viable organism but to produce embryonic stem cells.

–Embryonic stem cells (ES cells)•Are derived from blastocysts •Can give rise to specific types of differentiated cells

BiotechnologyAdult stem cells•Are cells in adult tissues •Generate replacements for nondividing differentiated cells

Adult stemcells in

bone marrow

Culturedembryonic stem cells

Different cultureconditions

Different types ofdifferentiated cells

Heart muscle cells

Nerve cells

Blood cells

http://www.rndsystems.com/dam_public/6515.jpg

BiotechnologyTherapeutic cloning

Biology and Society●Embryonic stem cells are currently derived from extra human blastocysts that sometimes result from in vitro fertilization techniques. From 2001 to 2009, stem cell research supported by U.S. agencies was restricted to only a small number of stem cell lines. (Meanwhile, other countries were going ahead with embryonic stem cell research.) But in March 2009, President Obama signed an executive order reversing federal opposition to embryonic stem cell research.

•Do you support the current U.S. governmental policy on stem cell research?

StronglyAgree

StronglyDisagreeA. E.C.B. D.

Recombinant DNA technologyDNA isolated from

two sources and cut by the same enzyme

Gene of interest

RecombinantDNA

Plasmid(vector)

Transgenic organisms

Useful products

Gene for pestresistance

Gene fortoxic-cleanup

bacteria

Some uses of proteins:

Protein for“stone-washing”

jeans

Protein fordissolving

clots

Some uses of genes:

Examples:In 1982, the world’s first genetically engineered pharmaceutical product was sold.

Humulin, human insulin:●Was produced by genetically modified bacteria●Was the first recombinant DNA drug approved by the FDA

Genetically Modified (GM) FoodsIn the United States today, roughly one-half of the corn crop and over three-quarters of the soybean and cotton crops are genetically modified.

●Corn has been genetically modified to resist insect

infestation.

Golden Rice

Genetically Modified (GM) Foods

Palmiter et al. (1982) Dramatic growth of mice that develop from eggs microinjected with metallothionine-growth hormone fusion genes. Nature 300: 611-615

“Supermice”

Other Examples:

Weeding Out Land MinesFirst Glowing Pet

http://www.glofish.com/

DNA PROFILING AND FORENSIC SCIENCE

DNA profiling:

•Can be used to determine if two samples of genetic material are from a particular individual

•Has rapidly revolutionized the field of forensics, the scientific analysis of evidence from crime scenes

Investigating Murder, Paternity, and Ancient DNA

DNA profiling can be used to:

•Test the guilt of suspected criminals•Identify tissue samples of victims•Resolve paternity cases•Identify contraband animal products•Trace the evolutionary history of organisms

DNA PROFILING AND FORENSIC SCIENCE

DNA isolated

DNA amplified

DNA compared

Crime scene Suspect 1 Suspect 2

●To produce a DNA profile,

scientists compare genetic markers, sequences in the genome that vary

from person to person.

Short Tandem Repeat (STR) AnalysisRepetitive DNA:

•Makes up much of the DNA that lies between genes in humans•Consists of nucleotide sequences that are present in multiple copies in the genome

Crime scene DNA

Suspect’s DNA

Same number ofshort tandem repeats

Different numbers ofshort tandem repeats

STR site 1 STR site 2

AGAT

AGAT GATA

GATA

Amplifiedcrime sceneDNA

Amplifiedsuspect’sDNA

Longerfragments

Shorterfragments

Short Tandem Repeat (STR) Analysis

GENOMICS

Genomics is the science of studying complete sets of genes (genomes).

●The first targets of genomics were bacteria.●As of 2009, the genomes of nearly one thousand species have been published, including:

Baker’s yeastMiceFruit fliesRice

The Human Genome ProjectBegun in 1990, the Human Genome Project was a massive scientific endeavor:

● To determine the nucleotide sequence of all the DNA in the human genome and ● To identify the location and sequence of every gene

At the completion of the project in 2004:●Over 99% of the genome had been determined to 99.999% accuracy● 3.2 billion nucleotide pairs were identified● About 21,000 genes were found● About 98% of the human DNA was identified as noncoding

Table 12.1

Chromosome

Chop up withrestriction enzyme

Sequencefragments

DNA fragments

Alignfragments

Reassemblefull sequence

http://www.otogenetics.com/

https://www.23andme.com/