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Genetics: Our Reproductive Futures?

Genetics: Our Reproductive Futures?. Transformations: Gender Reproduction and Contemporary Society Week 19. Structure of Lecture. Introduction Genetics: Cultural Representations Public Fear and Fascination Pre-conception Genetic Testing Pre-natal Genetic Testing

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Genetics: Our Reproductive Futures?

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  1. Genetics: Our Reproductive Futures? Transformations: Gender Reproduction and Contemporary Society Week 19

  2. Structure of Lecture • Introduction • Genetics: Cultural Representations • Public Fear and Fascination • Pre-conception Genetic Testing • Pre-natal Genetic Testing • Pre-implantation Genetic Diagnosis • Why is PGD so controversial? • The realities of PGD • Saviour Siblings • Sex Selection • Towards the Three Person Baby? • Conclusions

  3. DNA: Cultural Icon • Double-helix • Discovered by Watson and Crick • Dorothy Nelkin: Gene has become a cultural icon • BarabaraDuden: Pop gene • What does this image represent?

  4. Art Work by Gena Glover, former artist in residence, Genetics Unit Guy’s Hospital, London

  5. The X and Y chromosomes magnified many times

  6. Stamps issued in 2003 to celebrate 50th anniversary of discovery of structure of DNA • Ignores role of women • Rosalind Franklin took many of X ray images • Died as result of her work

  7. Born 5 July 1996

  8. ‘Celebrity Clone dies of drugs overdose’ • Headline in Nature, 18 February 2003 • Dolly put to sleep aged 6 • Suffering from incurable lung disease • Had six lambs, the ‘normal’ way • Body on display in National Museum of Scotland • Somatic (bodily) Cell Nuclear Transfer (cloning) is illegal in humans in UK

  9. Fear and Fascination

  10. Guardian, 3 May 2000

  11. Pre-conception Genetic Testing • To find out if carrying recessive gene for inherited conditions, eg. • Sickle-cell / Thalassaemia • Cystic Fibrosis • Huntingdon’s Disease • Tay Sachs • Spinal Muscular Atrophy (SMA) • If carrier and reproduce with another carrier 1 in 4 chance of passing on condition • Those with family history can be tested on NHS • Otherwise can pay privately • May be referred to as Pre-marriage Genetic Testing • Dangers?

  12. Pre-natal Genetic Testing • Helping to have a normal baby? • Or… • Generating anxiety? • Risk of miscarriage • ‘Slippery slope’ to abortion • Where to draw the line? • Regulating gene capital? (female) • Commodifying children? • Eugenics? • Boardman (2011): Women with genetic disabilities face pressure to use genetic testing to ensure a child without the condition • Use embodied knowledge of the condition and ‘a good life’ to resist • Terminating a foetus with the condition likened to ‘destroying oneself’

  13. Pre-implantation Genetic Diagnosis (PGD) • 8-cell embryo from IVF punctured and single cell extracted • Cell contains entire genetic make-up • Tested for specific genetic disorders • Embryos not affected transferred (up to • two) to woman’s uterus • Affected embryos discarded or donated to research • If disease only affects boys then embryos tested for sex and only female embryos selected (haemophilia; Duchennes Muscular Dystrophy) • In UK regulated in each case and each condition by HFEA • Can also be used to increase chances of successful pregnancy, to match a sibling to be a donor, to have less cancer predisposition

  14. Why is PGD controversial?

  15. The realities of PGD • People do not use PGD casually: • Very high failure rates (like all IVF) • High rates of attrition • Expensive • PGD patients have usually lost a foetus or a child – their desire is for a healthy baby whowill survive, rather than a ‘designer baby’ • PGD is a technology of selection, not design • As with IVF – an arduous physical process for women • New reproductive possibilities… • Alongside new risks and responsibilities

  16. Saviour Siblings: UK Pioneers • ZainHashmi (has Thalassaemia) • His parents had a second child disease-free but not a tissue match for Zai • Launched global search for tissue match, unsuccessfully • Raj and ShahanaHashmi sought permission to use PGD to select embryos that do not have disease and are a match to Zain • Legal wranglings but permission granted • IVF unsuccessful (probably due to Shahana’s age and egg quality by time permission granted)

  17. Saviour Siblings: US Procedure • Jamie Whitaker (b. 2003) as a ‘saviour sibling’ to his brother Charlie, who has Diamond Blackfan Anaemia (not an inherited condition) • Selection (using PGD) performed in US because illegal in the UK • Stem cells removed from umbilical cord and frozen • Waited 1 year to be sure Jamie did not have BA • Age 5 Charlie had chemo to ‘kill’ his own bone marrow, then the transplant • 5% risk that process would kill him • In 2011 Charlie 100% free of the Anaemia • HFEA now relaxed its approach

  18. Saviour Siblings: First full UK case • Max Matthews (b. 2009) as a ‘saviour sibling’ to his sister Megan (who had Fanconi anaemia) • Stem cells harvested from umbilical cord at Max’s birth • July 2010 stem cells and bone marrow from Max transplanted to Megan • First full ‘saviour sibling’ transplant in UK • What don’t we hear about? • Bone marrow harvesting is an invasive procedure

  19. Why are Saviour Siblings controversial?

  20. Determining the Sex of the Foetus • Ultrasound scan at 20 weeks • Amniocentesis (risk of miscarriage) • PGD of embryo following IVF • New blood test – of mother’s blood, from 7 weeks (genetic testing) - under medical supervision - bought privately eg. pay £179, provide drop of mother’s blood from finger prick, sent in mail - at 7-12 weeks 94.8% accurate when predicting a boy, 98.9% a girl At 20 weeks 100% accuracy • Pros and cons?

  21. Sex Selection: Abroad • ‘Sex Selection: Getting the baby you want. It’s one thing to wish for a baby boy or girl, quite another to make it happen. Amanda Mitchison meets the couples heading abroad – where the sex selection business is booming’ (Guardian, 3 April 2010) • Sex selection is illegal in the UK except on serious medical grounds

  22. Mitochondrial Replacement • Public consultation in 2012 on procedure to prevent transmission of mitochondrial disease • Foetus/baby would arguably have three genetic parents • Sperm from father, nuclear DNA from mother, mitochondrial DNA from donor • Mitochondria present in almost all human cells, generate energy • Two types of mitochondrial disease and this technique aimed at one; faults in mitochondria DNA inherited from mother • Technique replaces faulty maternal mitochondria with healthy mitochondria from a donor • IVF required • February 2014 HFEA published draft rules for consultation • Could begin from end of 2014, around 10 cases per year

  23. Pro-Nuclear Transfer

  24. Maternal Spindle Transfer

  25. Conclusions • Health, illness, the body and a wide variety of traits and characteristics are increasingly conceptualised in genetic terms • Reprogenetics evokes fear and fascination, spectre of ‘designer babies’ • Based on misunderstandings of the processes: selection not design • Careful regulation required to address ethical issues • Pre-conception screening has place for high-risk couples but might it become the new normal? • Genetic testing in utero generates hopes and fears • Genetic testing of embryos is likely to continue to expand, creating new choices, possibilities, dilemmas and responsibilities for society and for women • Cloning is illegal in UK • Reprogenetics of future may involve donated DNA

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