CTG Education FAQs


A: Nutritional genetics (nutrigenetics) is the study of how variants in your genes may increase or decrease your needs for specific nutrients and other bioactive food components (parts of foods and plants not already classified as nutrients). Making changes in your diet and lifestyle to meet these needs will help reduce your risk of certain diseases later on in life. Gene variants have also been shown to be useful in clinical practice, in managing weight loss and clinical conditions.

A: Nutritional genomics (nutrigenomics) is the study of the effects of nutrients and other bioactive dietary compounds on the expression of your genes (whether or not your genes are turned on or off, up-regulated or down-regulated) and your risk for certain diseases. People often use nutrigenomics as an umbrella term for both nutrigenetics and nutrigenomics; however, we propose that the efficacy and power of dietary intervention will entail health professionals being able to use nutrition to impact gene expression.

A: A gene is a segment of DNA (short for deoxyribonucleic acid) that contains information on hereditary characteristics such as hair color, eye color, and height, as well as susceptibility to certain diseases. Genes contain the instruction manual for how, when and where we make each of the many thousands of proteins required for life. There are approximately 20,000 – 25,000 genes found in our chromosomes.

Each gene is comprised of thousands of combinations of four genetic ‘letters’ that make up our genetic code: A, T, C and G, for adenine, thymine, cytosine and guanine, respectively. It is thought that every individual’s DNA contains approximately 3 billion of these genetic letters, known as nucleotides or bases. Each gene’s code combines the ‘letters’ A, T, C and G in various ways, spelling out the ‘words’ that specify which amino acid is needed at every step in the process of making the proteins required for our bodies to develop and function. Our genes may also tell us whether we are predisposed to specific health risks.

A: We all have small differences in the information our DNA contains (except identical twins), and it’s these differences that make each of us unique. Of the 3 billion nucleotides mentioned above, it is estimated that we are all different from each other in about 3 million of our genetic ‘letters’. For example, one genetic ‘letter’ (A,T,C or G) may be replaced by another. These variants can change metabolic processes in the body, just as altering one letter in a word can completely change its meaning; for instance, from ‘g’oat to ‘c’oat. When a variant affects only one genetic letter, as in the goat-to-coat example, it is called a SNP, pronounced ‘snip,’ (single nucleotide polymorphism). In other words, there has been a single nucleotide or base change. Nutrigenomics is concerned with how these small genetic changes in our DNA sequence can change the way our body responds to different foods and bioactive compounds.

A: In most cases, a SNP will have no effect on metabolic processes or on disease risk. In certain cases, these gene variants may be beneficial and protective, decreasing risk for certain diseases. However, sometimes a variant can affect a metabolic pathway that results in an enzyme not working as it should. The enzyme may, for example, work faster or slower than is best for the body. This alteration in enzyme activity, when combined with particular diet or lifestyle choices, may contribute to an increased risk susceptibility to developing common health conditions, such as cardiovascular disease, diabetes, osteoporosis, etc.

A: The gene MTHFR, which codes for the enzyme methylenetetrahydrofolate reductase, has a SNP identified as 677 C>T, which means that at nucleotide position number 677 on the MTHFR gene, a ‘C’ genetic letter has been substituted by a ‘T’ genetic letter. This substitution causes a decrease in MTHFR enzymatic activity. Among the consequences of this change are increased homocysteine levels and the potential for an increased risk for cardiovascular disease, certain cancers and many other conditions. What makes this SNP such an interesting one is the interaction with the B vitamin folate. Research has shown that in the presence of the ‘T’ genetic letter, homocysteine levels may be elevated when folate intake is low.

A: Initially genetic research was focused on what are known as inborn errors of metabolism. In these conditions a single gene variant may be responsible for the development of the disease. These diseases are passed down in families and usually display a strong family history. In the beginning, genetic research focused on discovering high penetrance gene variants that were causing these disorders. High penetrance gene variants are rare in the general population. What makes them distinct is that a high penetrance gene variant by itself can cause disease. In most cases the presence of the high penetrance variant means that an individual who has such a variant has an 80 – 90% chance of manifesting the disease. In these cases diet and lifestyle play a small role in the prevention and management of the disease. Examples of a high penetrance gene variant would be the variants of the BRCA1 and BRCA2 genes. The presence of specific variants of these genes confers a very high risk for the development of breast cancer. It is important to note, though, that only about 5% of all breast cancers are caused by these variants; the other 95% of breast cancers are the consequence of many genes (with low penetrance variants) interacting with diet and lifestyle choices.

Another example concerns the variants involved in the development of familial hypercholesterolemia (FH). The presence of a specific variant in the LDLR gene usually results in very high cholesterol levels and requires pharmacologic intervention. Dietary treatment certainly plays a role, but by itself it will not be able to prevent cardiovascular disease nor treat it.

However, these diseases occur in only a small fraction of the population. The major killer diseases are the chronic diseases such as heart disease, many cancers, and Type 2 diabetes. These conditions are caused by a combination of low penetrance genetic risk factors as well as adverse dietary and lifestyle choices. Nutrigenomics is therefore concerned with these chronic diseases of lifestyle. A low penetrance variant refers to the kind of variants that we are concerned with in nutrigenomics. These are variants that are fairly common in the population. They do not cause disease by themselves; their ability to increase susceptibility to disease results from their interaction with dietary and lifestyle choices and with other low penetrance gene variants.

Whereas familial hypercholesterolemia is caused by a single high penetrance gene variant, the majority of unfavourable lipid levels in the population is caused by a combination of low penetrance gene variants in genes such as CETP, LPL, and LIPC, interacting with an individuals diet and lifestyle. Similarly, it has been shown that low penetrance (and therefore fairly common) gene variants in metabolic pathways such as oxidative stress, detoxification and methylation, interact with an individuals diet and lifestyle to increase the risk of different cancers.

A: Low penetrance gene variants that are the focus of nutrigenomics cannot be used to diagnose disease for the reasons discussed above. They must be considered together with the diet and lifestyle choices that an individual makes. Rather, these variants provide useful information on disease risk susceptibility and can guide nutritional choices.

A: The April 2005 issue of the Journal of the American Dietetic Association was titled: Nutritional genomics in practice: Where do we begin? DeBusk suggested in 2005 that the future of dietetics was unquestionably intertwined with nutritional genomics. We believe that this is true for all health professionals, who will encounter nutrigenomics in their professional associations, journals, conferences, and most importantly from their patients.

There is a knowledge gap for most health professionals that limits their ability to choose the best commercial nutrigenetic test, meaningfully interpret the results, select an appropriate intervention and communicate the results and recommendations to their patients. Some would argue that all health professionals require at least a working knowledge of nutrigenomics, not being provided in their professional training.


A:  The Foundations course is the minimum we consider a health professional requires in order to meaningfully practice. There are four modules that address the following:

Module 1 – Introduction to Genetics – Dr Yael Joffe

An Introduction to Genetics will define and illustrate (with practical examples) the difference between nutrigenetics, nutrigenomics and epigenetics. In this module we will also explore the concept of food responsiveness, including examples to illustrate how they can be used in clinical practice, looking at gene-nutrient interactions for iron, lactose, salt and gluten, caffeine, and fatty acids.

Module 2 – Integration of Cellular Defence Mechanisms into Nutrigenomics   – Christine Houghton

This Integration of Cellular Defence Mechanisms module will provide a brief summary of cellular defence mechanisms, including: redox, inflammation, energy methylation, and detoxification. For each area we will explore the relevant genes, SNPs and diet-gene interactions. We will also briefly look at genes and SNPs that impact insulin resistance, the endothelium, and lipid metabolism.

Module 3 – The Genetics of Weight Management and Obesity – Dr Yael Joffe

Module three will explore Weight Management. Understanding the contribution of genetics to the susceptibility of becoming obese, and why individuals respond differently to weight management interventions. It will identify the many factors that contribute to obesity such as sleep, behaviour, appetite and satiety, thermogenesis and exercise responsiveness, and the diet-gene interactions that will impact these processes.

Module 4 – Clinical Implementation – Dr Yael Joffe

Module four addresses Clinical Implementation. Understanding the importance of the ethical, legal, and social aspects of Nutrigenetic testing. Students will be provided with criteria to evaluate individual gene variants for clinical usefulness. The second part of this module will teach the clinical implementation tools of the 6-Step Approach and 3-3-3. In addition to the theory, 3-3-3 case studies will be used to enable practitioners to become familiar with using this tool in their practice. Additional case study snap shots are also provided.

A. Students will receive the 150-page ebook SNP JOURNAL, free of charge. The SNP JOURNAL has been developed to provide students with a clear and concise review of 40 of the most commonly encountered SNPs in commercial nutrigenetic tests. The SNP JOURNAL ebook is provided free to all Foundations course students. Should they wish to purchase the printed book, this will be at an additional cost.

A. The Foundations online course is designed for health practitioners, educators and scientists whose services integrate cutting edge nutritional science into client or food solutions. Practitioners include: dietitians, medical doctors, specialist doctors, naturopaths, psychiatrists, nurses, nutritionists, dentists, chiropractors, and other allied health professionals. If you are unsure please email admin@ctgeducation.com.

A: If you are a registered full-time student you will qualify for a 30% discount, please email admin@ctgeducation.com with a copy of your student registration and you will receive a coupon code to register. If you are unsure if you qualify for the discount please email admin@ctgeducation.com.

A: The course is self-paced. You can start at any time, in any time zone, and go as slowly or as quickly as you like. At any time during and after the course you will be able to access the modules for revision. Students require access to a computer and adequate Internet capability. Students come from all countries around the world and have different work and family commitments. For this reason, we acknowledge that the course requires the greatest amount of flexibility.

There are four modules. At the end of each module students are required to complete a 10 question multiple choice quiz before proceeding to the next module. Once the Module 4 quiz is successfully completed, the student will receive a certificate of completion.

A: We estimate the course will require 40-50 hours of study. This will differ according to the student’s qualification, nutrigenomics knowledge level, and clinical experience. The Foundations course will take between two to three weeks full-time, or approximately two months part-time. No student will be penalized if he or she requires more time, but we do recommend that the course be completed over a two-month period.

A. At the end of each module, students will have to pass a 10-question quiz with 100%, in order to proceed to the next module. Once the Module Four quiz has been successfully completed, students will have completed the course and will receive a certificate to confirm this.

A. On completion of the Foundations course students will receive a certificate from CTG Education, signed by both Dr Yael Joffe and Christine Houghton. Accreditation for the Foundations in Nutrigenomics course is provided by CTG, the training organization specifically tailored to the needs of the practicing clinician. If however the student chooses to complete the Advanced Translational Nutrigenomics course, they will receive accreditation from ICN (Institute of Clinical Nutrigenomics). Completion of the Foundations course does not qualify for ICN accreditation.

A: Students will be able to communicate at any time with the course liaison, and if required with their instructors as well. In addition, a forum is provided for students to share their course experiences, and post questions for the instructors and each other.

A: The cost of the Foundations course is USD $595; this will include the SNP journal eBook which is valued at USD $79.50. Students have the choice of paying with PayPal, a credit or debit card, or a coupon code.



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