1. Human Cells Human genomics
Higher Human Biology
Human Cells
Human genomics

2. What do you know?
Human genomics is the study of the human genome working out the nucleotide sequences on DNA.
Relating the sequence to genes
Relating genes to their function
WHAT DO YOU KNOW ON THIS SUBJECT?

3. a. Sequencing DNA YOU SHOULD KNOW What bioinformatics is.
How modern DNA is analysed.
What systematic genome studies are
What the implications are of genome studies and personalised health treatments

4. Human genome project
Project to map all nucleotides in a typical human’s DNA
Started in 1990 finished in 2003
Shared between laboratories including UK and US
Using DNA sequencing tools including modified nucleotides, fluorescent dyes, electrophoresis and computers
The typical human genome consists of 3 billion nucleotides base pairs

5. Comparing individual genomes
Variations in DNA can be anaylsed down to single changes in base pair nucleotides
These are called single nucleotide polymorphisms (SNP)
1 million already identified with exact location and used as DNA markers
Used as a tool in biomedical research

6. Bioinformatics
Bioinformatics has increased the speed at which the genome can be analysed
The information is now analysed by computers and shared on the internet
3 areas to bioinformatics
Molecular biology (e.g. sequencing)
Statistical analysis
Computer technology

7. Bioinformatics
Computerisation allows data to be analysed very quickly including:
Protein-coding sequences similar to known genes
Start sequences of nucleotides where a coding sequence usually follows
Sequences lacking stop codons (as these usually have coding sequences before them)
Bioinformatics allows investigation into inheritance, evolutionary biology and personalised medicine

8. Systematics
Studying living things in relation to their diversity, relatedness and classification
Human genome sequences being compared to other genome sequences to look at evolutionary relationships and origins
Humans thought to originate in Africa
Developed to give distinct genetically different populations (millions of years)
Group moved out of Africa (approx. 100,000 years ago) to spread around the world

10. Mitochondrial DNA analysis
Mitochondrial DNA is inherited from female parent and not mixed with other DNA
Y chromosome in males also does not mix with other DNA during meiosis
Mitochondrial DNA can
be used to accurately
trace changes to DNA in
populations

11. Personalise medicine Your personalised genome sequence can be mapped.
It is becoming cheaper and faster to map using computerised machinery
Personalised medicine may be possible as human understanding of the genetic component of disorder/disease is better understood
How will that be a good or bad thing?

12. Mutations in humans
As the sequence is analysed changes will need to be identified for:
Neutral mutations (having no negative effect)
Harmful mutations (having a negative effect)
These could include non functioning protein code, non-coding for protein which give rise to genetic disorders or disease
Identified 2200 genetic disorders and diseases in humans
Need to analyse the cause for these (very complex)
Need to consider genetic and environmental influences

13. Pharmocogenetics
Studying the effects of pharmaceutical drugs on the human population
It is hoped in future drug efficacy will be able to be matched to genome of individuals for types and doses

14. The Future
DNA variations linked to diabetes, heart disease, cancer, obesity, etc?
What are the ethical issues related to knowing this information
Offspring
Employers
Insurance
Laws

15. What have you learned? What is bioinformatics?
What are the 3 areas that contribute to bioinformatics?
What are the computer programmes look for when analysing the coding sequences?
What is systematics in relation to genetics?
Why is it useful to know other species genomes?
What types of mutations is it important to distinguish between?
What is pharmacogenetics?
How could personalised medicine be realised?

16. Reinforcement Read chapter pages 63 to 70
Complete questions on page 70
Read Scholar section
Make own notes

17. Amplifying and detecting DNA sequences
What you should know
The process called Polymerase Chain reaction (PCR).
What DNA probes are and what they are used for.
The application of DNA profiling.

18. Polymerase Chain Reaction (PCR)
The technique used to produce multiple copies (amplify) of a piece of DNA
It is a computerised mechanised process that takes place outside the body (in vitro)
The process needs
The original DNA
Primers (small sections of DNA complimentary to the 3’ end of the DNA to be copied)
Nucleotides
DNA polymerase (heat stable)

20. PCR The original strand is heated to approx. 95oC to break H bonds
Cool to approx. 55oC to allow the primers to bind to its target sequence at 3’ ends
Heat to 72oC and nucleotides will join from primer ends by DNA polymerase
This produces 2 complete strands of DNA
Repeat the whole process many times to give amplification of DNA (multiple copies)
Think if the process was repeated 10 times how many DNA strands would be present at the end?
2, 4, 8, 16, 32, 64, 128, 256, 512, 1024

21. DNA probes DNA probes are short sections of single stranded DNA
They are capable of binding to a specific sequence of nucleotides
They can be labelled with fluorescent markers to all them to be detected
Collections of different DNA probes labelled with markers are used to identify a specific sequence on DNA

22. Uses of amplifying DNA - medical
Small quantities of DNA can be amplified
Specific sequences of DNA can be studied that are linked to genetic disorders/diseases
This can help with diagnosis if family history suggests disorder is present
This can help with estimating onset of genetic disorder/disease by identifying possible mutations in the genome

23. Uses of amplifying DNA - forensic
Human genome contains non-coding regions of DNA (introns)
These often have repeated sequences of code
They are randomly distributed in the genome
They are unique to individuals and can be used to identify a person’s DNA
They give the characteristic DNA profile banding patterns
This can in paternity disputes, missing person id, disaster missing persons id

26. What have you learned? What is PCR?
What are the 4 steps to the PCR process?
What are DNA probes?
What is needed to detect the DNA probes?
What are the applications of DNA profiling?
What are used to identify individuals when profiling DNA?

27. Reinforcement Read textbook pages 71 to 76 Answer questions on page 76
Complete summary on pages 76 and 77
Complete multiple choice questions chapter 5
Read Scholar
Go over PPT on blog
Make own notes from reading
Complete homework booklet on chapters 4 and 5 by Friday