Skip to 0 minutes and 12 secondsCHIARA MURGIA: Instructions to build and maintain an organism, including a human being, are contained in its DNA. DNA's an amazing molecule. It contains all the information to achieve these complex tasks. And because it's able to replicate itself, it's able to transfer the information across the generation. DNA is a long repetition of these four basic components. We call them nucleotides. The sequence order of nucleotides contain itself, the genetic information. A gene is a portion of DNA and corresponds to a unit of inheritance. Each gene carries the information to assemble a specific protein. So a gene has the information to assemble specific, one or more proteins. But the other way around is not true.
Skip to 1 minute and 4 secondsSo you can go back and get the information of DNA sequence from a protein. Scientists call this the central dogma. We call genome an organism's complete genetic information, contained in its DNA. Each cell of an organism has an identical, complete molecule of DNA containing all the information to be build that one organism. Scientists were able to identify all the human genes. There are about 20,000, much less than we thought. And we also call it the most oldest sequence. It doesn't actually contain genes. And we still cannot make sense of the role of all these non-coding DNA. And understanding the role of what we call the dark side of the human genome. It's probably the next big challenge.
Skip to 1 minute and 58 secondsWe understand now that partially the roll of these are non-coding DNA is to regulates gene activity. But there's still a lot we are learning.
What are genes and why are they important for health?
Watch Chiara provide an overview of genes and their function.
Genes are units of inheritance and are responsible for carrying genetic information from one generation to another. This means you inherit your genes from both your mother and father (and they inherit it from their mother and father and so forth), and the information stored in your genes is what makes you – you.
Genes are sections of DNA, and one whole copy of DNA includes all the genes to make instructions for you. DNA provides the instructions to turn a one-cell embryo into a 100 trillion – cell (yes that is how many cells are in your body) adult. These instructions include how the body deals with and responds to pathogens, specific foods, pollutants and other elements of your environment.
Genes mostly hold instructions to make proteins in the body. This is important for health as proteins and enzymes are involved in many body processes. If individuals either lack the genes or have faulty genes coding, instructions for certain proteins or enzymes then this may have detrimental effects for health.
99.9% of all our genetic material is identical in humans, which is what identifies us as a species. The 0.1% of our genetic material is different from person to person is what makes each person unique (causing differences in things like our metabolic rate, hair and eye colour, height and also our nutrition needs). These differences between people are called gene variations or polymorphisms.
Gene variations are important to consider when thinking about health. Some gene variations may cause rare diseases (and are often referred to as mutations), while others are more common (and are just described as polymorphisms). Gene mutations and polymorphisms may interact with other genes and with factors in our environment (including diet, smoking, physical activity etc), to play a role in the development of complex disease such as Type 2 diabetes, asthma, cardiovascular disease.
Find out more
In the See also section of this step, you can access a link to a guide produced by the National Human Genome Research Institute article that provides an overview of the human genome.
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