Genes & Technology

1. Genes & Technology Technology to Understand the Human Genome

2. Chromosomal Mutations • Large sections of DNA contain 100,000’s of bases and multiple genes. • Chromosomal mutations are large scale changes to chromosomes.

3. Types of Chromosomal Mutations • Deletion—remove large section of DNA • Duplication—copy a section of DNA 2 times • Inversion—reverse the order of a section of DNA • Insertion—move a section of DNA to a different chromosome • Translocation—different chromosomes trade sections • All mutations move multiple genes in a section.

4. Check your understanding E • Match the letter to the mutation. • Duplication • Deletion • Translocation • Inversion • Insertion

5. Karyotype • A photomicrograph is taken of the chromosomes during mitosis. • The chromosomes are cut apart and sorted into homologous pairs. • Criteria for pairing: • Size • Banding • Location of centromere SKY Spectral Karyotype is a recent improvement.

6. Normal or not? • Humans have 23 chromosomes in homologous pairs. • Nondisjunction is an error during meiosis • Normal meiosis tetrad divided into 2 pairs, pairs divided into 1’s • Error results in a gamete with 3: trisomy 1: monosomy Normal 3 1 Trisomy Monosomy

7. Errors in Chromosome Number • Trisomy results from fusing a gamete with 2 chromosomes plus a gamete with the normal 1 chromosome = total 3. • Trisomy 21—Down’s Syndrome. Effects many body systems. • Other trisomies are possible, 13, 18, and sex chromosomes. • Karyotype has 47 chromosomes. • Monosomy results from fusing a gamete with 0 chromosome with the normal 1 chromosome gamete = total 1 • Turner’s Syndrome—single X is the only survivable monosomy. • Karyotype has 45 chromosomes. • Turner’s women can live relatively normal life. • Effects multiple body systems. Actress Linda Hunt, successful person with Turner’s Syndrome.

8. Make your own karyotype • Visit the Learn.Genetics website and try the computer model for building a karyotype. • This diagnostic study used for genetic counseling. • Karyotype can be used to: • Diagnose nondysjunction—trisomy or monosomy • Diagnose chromosomal mutations • Diagnose 1000’s of genetic disorders • Complete the karyotype and make a diagnosis • http://www.biology.arizona.edu/human_bio/activities/karyotyping/patient_a/patient_a.html

9. Gel Electrophoresis • Method of analyzing patterns in DNA • Test also called DNA fingerprinting, DNA profile, DNA barcoding • Sample of DNA from one source • Make many copies • Cut in pieces with an enzyme • Prepare Gel and bath set up • Add DNA sample and DNA of known sizes to separate wells • Connect electricity, let the DNA move • Large pieces are slow and small pieces move faster.

10. Results of Gel Electrophoresis • Bars of stained DNA are visible. • Reference DNA of known size allows estimate of unknown DNA sizes by comparison. • Compare the patterns. • Find 2 patterns that are alike.

11. Check your understanding • Take a look at the DNA fingerprint analysis. • M is the mother, Jennifer Barker. • C is the child, Andrew Barker. • AF is the alleged father, Steven Barker. • Remember, to conclude that the alleged father is truly the father, every band in the child's fingerprint that does not match in the mother's fingerprint must match in the father's. • Could this be the true father?

12. Types of DNA in Genome • Genome is the total of all DNA • Autosomal DNA—chromosomes #1 to #22 • Crossing over in meiosis introduces genetic diversity. • X chromosomal DNA—from mother to sons and daughters • Maternal line inheritance • Y chromosomal DNA—from father to son • Paternal line inheritance • Mitochondrial DNA—from mother to sons and daughters • Little to no mutation in DNA contained in the mitochondria.

13. Human Genome • Human Genome Project took 13 years and cost $3 billion. • First completion of decoding the human genome was done by multi-national teams in 2000. • Less expensive sequencing equipment has increased the rate of discovery. • The cost for a human genome sequencing has reached $1,000. • Personalized genomic medicine is starting to be practiced. • How to sequence the human genome—Mark Kiel, TedEd • http://www.youtube.com/watch?v=MvuYATh7Y74

14. Gene Therapy • Inserting a new gene into an existing organism using a delivery system. • Delivery—harmless virus or stem cells • Conditions that may be treated are genetic in origin and • Are well understood • Faulty gene identified & working gene available • Cells needing treatment are accessible • Delivery method available • Only somatic cells, no sex cells—no risk to future

15. Gene Therapy The technique may be used • to replace a faulty gene • Example: Bubble children • Severe Combined Immune Deficiency first trial in 2000. • 10 children, 7 cured, and 2 developed leukemia • Only treatment resulting in full cure. • to introduce a new gene whose function is to cure or to favorably modify the clinical course of a condition • Example: gene for improving attack on cancer • to inactivate a faulty gene

16. Genetic Engineering • Selective breeding by people to modify animals or crops • Wild maize to modern corn • GMO—genetically modified organism • Current technique for inserting new gene • Herbicide resistant crops for easier weed control, pest resistant, or adapted to environmental conditions. • 10% of world crops in 2010 were GM crops.

17. Resources • Staff, 2014, Human Genome Project, National Human Genome Research Institute, http://www.genome.gov/10001772 • Staff, 2014, Make a Karyotype, Genetic Science Learning Institute, University of Utah, http://learn.genetics.utah.edu/content/chromosomes/karyotype/ • Staff,2014,Chromosomes and Inheritance, Genetic Science Learning Institute, University of Utah, http://learn.genetics.utah.edu/content/chromosomes/ • Staff, 2012, Gene Therapy, Centre for Gene Therapy, New South Wales, Australia, http://www.genetics.edu.au/Publications-and-Resources/Genetics-Fact-Sheets/FactSheet27 • Staff, 2014, Gel Electrophoresis, Biology Block, http://biologyblock.com/?p=1109