Human Molecular Human Molecular Genetics Genetics

Section 14–3 Section 14–3

This section explains how genetic engineering This section explains how genetic engineering techniques are being used to study the genes techniques are being used to study the genes and chromosomes in the human genome. It also and chromosomes in the human genome. It also describesdescribeshow this information is used for gene therapy.how this information is used for gene therapy.

Human DNA Analysis Human DNA Analysis

Biologists search the volumes of the Biologists search the volumes of the human genome using ______ .human genome using ______ .

• sequences of DNA basessequences of DNA bases

Human DNA AnalysisHuman DNA Analysis

Why might prospective parents decide Why might prospective parents decide to have genetic testing?to have genetic testing?

Genetic tests can determine whether Genetic tests can determine whether prospective parents risk passing prospective parents risk passing alleles for genetic disorders to their alleles for genetic disorders to their children.children.

Human DNA AnalysisHuman DNA Analysis

Circle the letter of each sentence that is true about Circle the letter of each sentence that is true about genetic testing.genetic testing.

• Labeled DNA probes can be used to detect specific Labeled DNA probes can be used to detect specific sequences found in disease causing alleles.sequences found in disease causing alleles.

• Some genetic tests use changes in restriction enzyme Some genetic tests use changes in restriction enzyme cutting sites to identify disease causing alleles.cutting sites to identify disease causing alleles.

• DNA testing makes it possible to develop more effective DNA testing makes it possible to develop more effective therapy and treatment for individuals affected by therapy and treatment for individuals affected by genetic disease.genetic disease.

DNA FINGERPRINTINGDNA FINGERPRINTING

What is DNA fingerprinting? What is DNA fingerprinting?

• It is the identification of individuals It is the identification of individuals by a method that analyzes sections by a method that analyzes sections of DNA that have little or no known of DNA that have little or no known function but vary widely from one function but vary widely from one individual to another.individual to another.

DNA FINGERPRINTINGDNA FINGERPRINTING

Circle the letter of each source for a Circle the letter of each source for a DNA sample from an individual.DNA sample from an individual.

• a. a. blood blood • b. b. sperm sperm • d. d. hair with tissue at the basehair with tissue at the base

DNA FINGERPRINTINGDNA FINGERPRINTING

Is the following sentence true or false?Is the following sentence true or false?

• DNA evidence is not reliable enough DNA evidence is not reliable enough to be used to convict criminals.to be used to convict criminals.

• FALSEFALSE

The Human Genome Project The Human Genome Project

What is the Human Genome Project? What is the Human Genome Project?

• It is an ongoing effort to analyze the It is an ongoing effort to analyze the human DNA sequence.human DNA sequence.

Human Genome ProjectHuman Genome Project

Circle the letter of each sentence that is true Circle the letter of each sentence that is true about the Human Genome Project.about the Human Genome Project.

Researchers completed the genomes of Researchers completed the genomes of yeast and fruit flies during the same timeyeast and fruit flies during the same timethey sequenced the human genome.they sequenced the human genome.

A working copy of the human genome was A working copy of the human genome was completed in June 2000.completed in June 2000.

Human Genome ProjectHuman Genome Project

What were the three major steps in the process of What were the three major steps in the process of sequencing the human genome?sequencing the human genome?

• Widely separated regions of DNA on each Widely separated regions of DNA on each chromosome were sequenced.chromosome were sequenced.

• Random fragments of DNA were Random fragments of DNA were sequenced.sequenced.

• Computers found overlapping regions Computers found overlapping regions between the fragments and positioned them between the fragments and positioned them relative to the known markers.relative to the known markers.

Human Genome ProjectHuman Genome Project

What is an open reading frame, and What is an open reading frame, and what is it used for? what is it used for?

• It is a series of DNA bases It is a series of DNA bases that will produce an mRNA sequence. that will produce an mRNA sequence. Scientists use it to locate genes.Scientists use it to locate genes.

Human Genome ProjectHuman Genome Project

The mRNA coding regions of most The mRNA coding regions of most genes are interrupted by genes are interrupted by IntronsIntrons..

Human Genome ProjectHuman Genome Project

List three other parts of the gene that List three other parts of the gene that researchers look for.researchers look for.

• PromoterPromoter

• ““Start” site for transcriptionStart” site for transcription

• ““Stop” site for transcriptionStop” site for transcription

Human Genome ProjectHuman Genome Project

Why are biotechnology companies Why are biotechnology companies interested in genetic information? interested in genetic information?

• They are trying to use this They are trying to use this information to develop new drugs information to develop new drugs and treatments for diseases.and treatments for diseases.

Human Genome ProjectHuman Genome Project

Is the following sentence true or false? Is the following sentence true or false?

Human genome data is top secret Human genome data is top secret and can be accessed only by certain and can be accessed only by certain people.people.

• FalseFalse

Gene Therapy Gene Therapy

What is gene therapy?What is gene therapy?

• In gene therapy, an absent or faulty In gene therapy, an absent or faulty gene is replaced by a normal, gene is replaced by a normal, working gene.working gene.

Gene TherapyGene Therapy

Circle the letter of each sentence that is true about Circle the letter of each sentence that is true about gene therapy.gene therapy.

• When the normal copy of the gene is inserted, the When the normal copy of the gene is inserted, the body can make the correct protein, which body can make the correct protein, which eliminates the disorder.eliminates the disorder.

• Viruses are often used to carry the normal genes Viruses are often used to carry the normal genes

into cells.into cells.

Gene TherapyGene Therapy

Have all gene therapy experiments been Have all gene therapy experiments been successful? successful?

• NoNo

• attempts to treat cystic fibrosis by spraying attempts to treat cystic fibrosis by spraying genetically engineered viruses into genetically engineered viruses into breathing passages have not produced abreathing passages have not produced alasting cure.lasting cure.

Gene Therapy EthicsGene Therapy Ethics

Ethical Issues in Human GeneticsEthical Issues in Human Genetics

What other changes could be made to the What other changes could be made to the human genome by manipulating humanhuman genome by manipulating humancells?cells?

• Biologists could try to engineer taller Biologists could try to engineer taller people or change eye color, hair texture, people or change eye color, hair texture, sex, blood group, or appearance. They sex, blood group, or appearance. They could even clone human beings.could even clone human beings.

Gene Therapy EthicsGene Therapy Ethics

What is the goal of biology?What is the goal of biology?

• It is to gain a better understanding It is to gain a better understanding of the nature of life.of the nature of life.

Gene Therapy EthicsGene Therapy Ethics

What is the responsibility of society in What is the responsibility of society in biology? biology?

• Society will have to learn to use wisely Society will have to learn to use wisely the tools that science has given it. It the tools that science has given it. It will have to develop an ethical will have to develop an ethical consensus of what should and should consensus of what should and should not be done with the human genome.not be done with the human genome.

Gene Therapy EthicsGene Therapy Ethics

Is the following true or false? Is the following true or false?

• Scientists should be expected to Scientists should be expected to make all ethical decisions regarding make all ethical decisions regarding advances in human genetics. advances in human genetics.

• falsefalse