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Two Thirds of Australians Develop a Skin Cancer During Their Lives And, at a Conservative Estimate, 1700 Cases Prove Fatal Each Year

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Two Thirds of Australians Develop a Skin Cancer During Their Lives And, at a Conservative Estimate, 1700 Cases Prove Fatal Each Year SKIN DEEP A STUDY GUIDE by mArguerite o’hArA http://www.metromagazine.com.au http://www.theeducationshop.com.au What does our skin colour The background information and the tell us about ourselves and + fact sheet about skin (which appear where we come from? later in this guide) are important for CurriCulum guidelines introducing the topic and summarising The skin is the largest some of the main areas investigated organ of the human body. Skin Deep would be suitable for in the documentary. Teachers could middle and secondary students of: select from the student activities in this We know that sunlight can • Biology guide, which move from understanding burn our skin, and that the science of skin to discussing its • General Science broader implications. various creams and make- • SOSE/HSIE up can change its colour • Health and Human Development SYnopsis and tone, but how much do • Psychology we really know about why For hundreds of years, human skin colour has been used as a marker of our skin comes in so many race. Now, science is uncovering the colours and shades? What he documentary explores how intricate relationship between skin causes skin colour and long-term scientific study has colour and environment. When our how does it determine our Tunlocked the mystery of the ancient ancestors in Equatorial Africa range of skin colour in humans. This lost their body hair and ventured out sense of identity? Is skin is a ‘science mystery’ film that poses into the open savannah, their skin had colour simply a matter of questions, offers answers and then to become dark to resist strong UV your ancestors’ birthplace moves deeper into the science to un- radiation. Perfectly adapted to the en- and its distance from the derstand the widely accepted notions vironment, the black skin of Africans is of skin colour as an indicator of human one of nature’s greatest achievements equator, or is there a more adaptation to different environments. in ensuring the survival of the human complex explanation? species. For centuries, skin colour was essen- tially considered as a marker of race; This may not sound new, but in 2000 this program shows that many of our Penn State University anthropologist assumptions about skin colour are of- Nina Jablonski put forward a startling ten too simple or wrong. The program new explanation as to why human is a fascinating and accessible scien- skin has so many colours. Her study SCREEN EDUCATION tific and sociological study, as colourful suggested that pigmentation did not and absorbing as the variety of skin evolve to prevent skin cancer, but pri- colours it investigates. marily to help the human body main- tain the right balance of two crucial 2 Prof keith cheng Skin Deep crew with nina JaBlonski dr carles lalueza fox dr michael holick Background information The filmmakers Dr Michael Holick – Professor of Skin Deep is a co-production The participants Medicine, Physiology and Biophys- between Electric Pictures (Australia) ics; director of the General Clinical and DocLab (Italy). Several eminent researchers from a va- Research Unit and director of the Bone The documentary runs for 52 minutes riety of specialised fields appear in this Health Care Clinic and the Heliothera- documentary, most notably Nina Jab- py, Light and Skin Research Centre at DirecTor lonski, who has devoted many years Boston University Medical Centre. Franco Di Chiera of study and collaborative work to WriTers anD researchers the study of the evolution of skin. The Dr Holick determined the mechanism Barbara Bernardini, Greg Colgan and experts telling this story come from the for how vitamin D is synthesised in the Franco Di Chiera USA, Spain and Australia. Research skin, and demonstrated the effects ProDucers often involves collaborating across of aging, obesity, latitude, seasonal continents and across a number of change, sunscreen use, skin pigmenta- Marco Visalberghi, Andrew Ogilvie and Andrea Quesnelle scientific and medical specialties. tion and clothing on this vital cutane- ous process. He has established global execuTive ProDucers nina Jablonski – Professor and Head recommendations advising sunlight Andrew Ogilvie and Marco Visalberghi of Anthropology, Penn State University, exposure as a key source of vitamin D. eDiTors USA. He has also helped increase aware- David Fosdick and Lawrie Silvestrin ness in the paediatric and medical A biological anthropologist and palaeo- communities regarding vitamin D DirecTor of PhoTograPhy biologist, Jablonski studies the evolution deficiency and its role in causing meta- Torstein Dyrting of adaptations to the environment in bolic bone disease and osteoporosis non-human and human primates. She in adults as well as increasing the risk has worked to shed light on the nature to adults and children of developing a vitamins essential for reproduction and of ‘successful’ and ‘unsuccessful’ ana- range of diseases. body development. As a result, skin tomical and physiological adaptations to colour developed as a perfect compro- the environment through time. In the last professor Keith Cheng – Director of mise, allowing enough sunlight in to fifteen years, she has been increasingly Experimental Pathology at Penn State stimulate the production of vitamin D, absorbed in studies of the evolution of College of Medicine. but screening the body from harmful human skin and skin colour. Her 2006 rays that destroy folic acid – a vitamin book Skin: A Natural History (Univer- Cheng has been a leader in genetics necessary for reproductive success. sity of California Press) won the W.W. and genomics, using the zebrafish Howells Book Award of the American to study cancer. In the course of this Focusing on ground-breaking research Anthropological Association. work he discovered SLC24A5, which and accounts from scientists around appears to have played a key role in the world, this documentary reveals Dr Carles Lalueza-Fox – Barcelona the evolution of light skin in people that the evolution of skin colour is sole- Institute of Evolutionary Biology. of European ancestry. He is keen to ly an adaptation to the environment. contribute to the demystification of It drives home a powerful message: Best known for his work on the skin colour and race, which he hopes SCREEN EDUCATION judging people on the basis of colour Neanderthals, Lalueza-Fox works on will diminish racism. is not only morally unacceptable, it is paleogenetic puzzles. He is currently scientifically wrong. working on the Neanderthal Genome Project. 3 Biasutti records skin colour Prof fiona stanley professor Fiona Stanley – Director of Albinism – an almost total lack of mel- Folate – Folic acid, one of the B vita- the Telethon Institute for Child Health anin caused by a major DNA malfunc- mins that is a key factor in the synthe- Research in Perth and professor in the tion. With no natural defence against sis (the making) of nucleic acid (DNA School of Pediatrics and Child Health the sun’s rays, people with albinism and RNA) and which is commonly at the University of Western Australia. run a 1000-fold risk of developing skin found in leafy green vegetables and cancer compared to those with darker whole grains. Lack of adequate folic In 2003, Stanley was Australian of the skin. acid during pregnancy has been found Year. While she trained and worked to increase the risk of the baby having as a medical doctor, her move into Vitamin D – vitamin D promotes ab- a birth defect involving the spinal cord research was prompted by a desire to sorption and use of calcium and phos- and brain, i.e. a neural tube defect prevent – rather than to simply treat phate for healthy bones and teeth. The such as spina bifida or anencephaly. – many of the recurring conditions main source of vitamin D is the sun. that she saw in children, particularly Anthropology – the scientific study in those from disadvantaged environ- Vitamin D is found in milk (fortified), of the origin, behaviour, and physical, ments. She has established a number cheese, whole eggs, liver, salmon and social and cultural development of of comprehensive databases that track fortified margarine. The skin can syn- humans. maternal and child health. This has en- thesise vitamin D if exposed to enough abled her and her Institute colleagues sunlight on a regular basis. Adaptation – the adjustment of an to look at the causes and prevention organism to its environment, or the of birth defects and major neurologi- Calcium – A chemical element es- process by which it enhances such cal disorders such as cerebral palsies sential for the normal development fitness. and neural tube defects, research that and functioning of the body, typically resulted in a worldwide campaign to present in the blood at a concentra- encourage women to take folate prior tion of about 10mg/100ml. Calcium to and during pregnancy. is an important constituent of bones and teeth, and it is essential for many key terms metabolic processes, including nerve function, muscle contraction and blood Skin colour – infinite variations from clotting. dark to light, mostly brown and beiges. There is no such thing as truly red, UVA and UVB rays – the sun emits yellow, black or white in skin colour. ultraviolet radiation in the UVA, UVB Rather there is an infinitely graded and UVC bands. The earth’s ozone spectrum of shades from dark to light. layer stops 97 to 99 per cent of this UV radiation from penetrating through Melanin – the main determinant of skin the atmosphere. 98.7 per cent of the colour. There are two types of pig- ultraviolet radiation that reaches the ments, eumelanin, which is brown or earth’s surface is UVA. While we need black, and pheomelanin, which is red a certain amount of UV light to pen- SCREEN EDUCATION or yellow. The relative amount of these etrate our skins, too much can result in two types of melanin determines the the development of skin cancers.
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