Genetics and Paediatric Health: Section 1 Suggested reference: Rockman-Greenberg, C., Avard, D., Hanvey, L., Marcotte, M., & Fitzpatrick, J. (2014). Genetics and paediatric health: Section 1: A genetics primer. In The Health of Canada’s Children and Youth: A CICH Profile. Retrieved from http://profile.cich.ca/en/index.php/chapter2 Module contributors:  Writing and editing:  Denise Avard Jennifer Fitzpatrick  Louise Hanvey    Cheryl Rockman-Greenberg    Graphic design:   Shelley Callaghan Louise Hanvey Meghan Marcotte Bert Schopf Website development:  Accel Web Marketing   Project development, research, and review: Expert Advisory Committee Laura Arbour Denise Avard Pascal Borry Pranesh Chakraborty Jennifer Fitzpatrick  William Fraser Jan Friedman Louise Hanvey    Anne Junker Bartha Maria Knoppers Elaine Orrbine Cheryl Rockman-Greenberg  Jacques P. Tremblay Brenda Wilson Durhane Wong-Rieger Other Denise Alcock Jeannine Fraser Aspasia Karalis  Meghan Marcotte Kelly McClellan  Vaso Rahimzadeh Karine Sénécal Janice Sonnen Robin Walker

An individual’s genetic make-up forms what is known as the genome An individual’s genetic make-up forms what is known as the genome. The human genome is made up of nearly 20,000 genes. Though specific genes control specific parts of human development and health, they are grouped together into physical structures called chromosomes and are located in the nucleus of each cell. Humans have 23 pairs of chromosomes, so every individual has two copies of every gene and a child receives one copy of each gene from each parent. A gene is made of deoxyribonucleic acid (DNA), which is the genetic instruction manual. There are a number of websites where you can find more information about the genome, for example: SickKids, the Genetics section (http://www.aboutkidshealth.ca/En/HowTheBodyWorks/GeneticsIntroduction/Pages/default.aspx) (If a user profile box pops up, you can press ‘cancel’ or create a user profile to access this site.) Utah Genetics Education, Tour of Basic Genetics (http://learn.genetics.utah.edu/content/basics/)  

Gene expression is the process whereby the information in a gene produces the final gene product – a protein. Gene expression refers to genes being turned “on’” or “off” – that is, stimulated to produce protein. Healthy development of all organs in the body depends on which and when certain genes are expressed. You can think of genes acting as an orchestra, turning on and off, and producing proteins that act together – in concert-like fashion – in the development of an individual. Many factors can influence the individual instruments (genes) in this complex orchestra. Research shows that environmental factors and early experiences have the power to chemically influence gene expression and hence control their function. Genes provide the directions for building every molecule the human body requires. There are hundreds of different kinds of cells in the body, and it is the variety in gene function and expression that determines these differences. There are a number of websites where you can find more information about genes, for example: Utah Genetics Education, the Epigenetics section (http://learn.genetics.utah.edu/content/epigenetics/) DNA Learning Centre (http://www.dnalc.org/resources/genescreen/punnett-genetic-disease.html)