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DNA Testing: Glossary 101

DNA testing has grown in popularity as it offers information about an individual's genetic predispositions related to various aspects of health and well-being. It provides insights into how the unique genetic makeup of each individual may influence their risk for certain conditions, such as type 2 diabetes, gluten sensitivity, detoxification processes, and more, as well as their response to specific lifestyle choices, including diet, exercise, sleep patterns, stress management, and more.


Why use a DNA test in your practice? 

A DNA test will allow you to learn about your client's genetic makeup and provide personalised information about their health, risk factors, and other traits. By understanding these elements, you can be more proactive in supporting their health by implementing lifestyle changes such as food choices, exercise, stress reduction, and others that counteract the effects of their genes.

Additionally, research has shown that personalised nutrition advice produces larger and more meaningful changes in dietary behaviour than a conventional approach. Therefore, this could increase the likelihood of client compliance, leading to better results and ultimately improved overall health.

DNA tests come with a plethora of new terminology. This blog post will help you decipher the meaning of each term and understand how they relate to each other.



DNA is composed of two linked strands that wind around each other, resembling a twisted ladder — a shape known as the double helix. The double-stranded helix is composed of repeating units called nucleotides, which are the fundamental building blocks of DNA.

Each nucleotide consists of a sugar molecule (deoxyribose), a phosphate group, and a nitrogenous base. There are four types of nitrogenous bases in DNA, which can be grouped into two categories:

  • Purines: Adenine (A) and Guanine (G)
  • Pyrimidines: Cytosine (C) and Thymine (T)

On the other hand, base pairs are formed when two complementary nitrogenous bases come together and bind within the DNA molecule. Adenine (A) always pairs with thymine (T), and cytosine (C) always pairs with guanine (G). These pairings are held together by hydrogen bonds.


Our bodies consist of 100 trillion cells, each with its own complete set of genetic instructions. This comprehensive genetic material, also referred to as DNA, is known as the genome and is tightly packed into the nucleus of the cell within structures called chromosomes.

Most human cells contain 46 chromosomes, organised into 23 pairs, collectively containing approximately 20,000 to 25,000 genes. Some genomes are extremely small, as seen in viruses and bacteria, whereas other genomes, like the human genome, can consist of 3.2 billion DNA bases. Thus, if it were feasible to unwind the DNA from a single cell and extend it, it would measure about 2 metres (6 feet) in length.


The study of how an organism grows and develops and how chemical reactions switch parts on or off in strategic locations and at strategic times within the genome. Epigenetics ‘tags’ genes and reacts to the outside world, lifestyle, diet and environment, without changing the underlying DNA sequence. 


An individual inherits two alleles for each gene, one from each parent and therefore, each pair of alleles will represent the genotype of a specific gene. Genotypes are described as homozygous if there are two identical alleles at a particular location and as heterozygous if the two alleles differ.

Here are the 3 classifications of allele pairs:

  • Homozygous Wild type - Matches wider population
  • Heterozygous - One Allele variation
  • Homozygous - Two Allele variations

These classifications depend on whether you are inheriting variations from neither, one or both parents. 


A phenotype is the manifestation of the genotype in the observable traits of an individual (such as eye colour, hair colour, glucose response, food and drug metabolism, etc.).

Allele variations can include an individual or multiple nucleotide changes within a section of DNA. 

Single nucleotide polymorphism (SNP) 

A single base change in a DNA sequence that occurs in a significant proportion (more than 1%) of a large population, SNPs occur on average once in every 300 nucleotides and form the basis of how DNA testing is interpreted.

To summarise, a genome consists of DNA; DNA includes several genes; genes encompass multiple alleles, and one or more SNPs can occur within an allele.


Regenerus have introduced the Omnos DNA test to our platform this September — the first fully comprehensive DNA test we've distributed! Buy the DNA test here

Contact for any pressing enquiries!




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