1. © 2009 NHS National Genetics Education and Development CentreGenetics and Genomics for Healthcare www.geneticseducation.nhs.uk Inherited Pre-disposition to Bowel CancerFamilial Adenomatous Polyposis (FAP) This PowerPoint file contains a number of slides that may be useful for teaching of genetics concepts. You may use these slides and their contents for non-commercial educational purposes.

2. © 2009 NHS National Genetics Education and Development CentreGenetics and Genomics for Healthcare www.geneticseducation.nhs.uk Familial Adenomatous Polyposis This presentation includes: The genetic development of familial cancer (2 hit hypothesis) A pedigree showing FAP in a family A clinical photograph of a piece of resected bowel with multiple polyps Two pedigrees used to assess risk and highlight which relatives are at risk and need bowel screening Surveillance/Screening for FAP

3. © 2009 NHS National Genetics Education and Development CentreGenetics and Genomics for Healthcare www.geneticseducation.nhs.uk The genetic basis of the dominantly inherited familial cancer syndromes An altered allele is inherited and is found in all body cells that contain genetic material. When the second (previously normal) allele of the gene pair becomes inactivated in a particular somatic cell, this can lead to loss of control of cell growth and unchecked cell proliferation. Clone of cancer cells from this one cell Inherited altered allele Second allele of the pair becomes inactivated (somatic mutation)

4. © 2009 NHS National Genetics Education and Development CentreGenetics and Genomics for Healthcare www.geneticseducation.nhs.uk Fig. 12.2 ©Scion Publishing Ltd Photo. courtesy of Medical Illustration, Manchester Royal Infirmary Familial adenomatous polyposis coli (a)Pedigree of the Xenakis family. (b)Part of a surgically resected colon with polyps.

5. © 2009 NHS National Genetics Education and Development CentreGenetics and Genomics for Healthcare www.geneticseducation.nhs.uk Martins family d. 34yrs Martin Suzanne Jamie 12 Sophie 9 Alex 5 36 (colectomy @ 25) Who is at risk?

6. © 2009 NHS National Genetics Education and Development CentreGenetics and Genomics for Healthcare www.geneticseducation.nhs.uk Martins family d. 34yrs Martin Suzanne JamieSophieAlex 1295 36 (colectomy @ 25) Who is at risk?

7. © 2009 NHS National Genetics Education and Development CentreGenetics and Genomics for Healthcare www.geneticseducation.nhs.uk Surveillance for FAP Annual sigmoidoscopies from age 10 to 12. Colonoscopies once polyps detected. Surveillance of remaining gut following colectomy. http://www.nice.org.uk/nicemedia/pdf/CSGCCfullguidance.pdf Is there an alternative? Genetic testing