The world of genetics - what you need to know

Have you ever wondered why a particular treatment or diet may have worked for one client but not another? Well, along with environmental factors, DNA has a role to play in the health of skin and how well it ages, says Team Gene Skin owner Karen Harrison MSc

DNA testing takes us a step further, arming us with the knowledge of our predispositions to our skin health and ageing. Recent studies of twins have revealed that up to 60% of the variation in skin ageing can be attributed to genetic factors (Naval, Alonso and Herranz, 2014).1Now, the aesthetics industry can get a slice of this personalised medicine approach as skin DNA testing hits the market.

Here’s what you need to know about genetics and how the personalised results from testing can improve client outcomes.

HISTORY OF GENETICS

The observation that particular traits tend to be found among families dates back to the days of Aristotle, but it was in 1865 that, while experimenting on pea plants, Austrian monk Gregor Mendel discovered how traits are passed from one generation to the next. He established the principles of inheritance which formed the cornerstone of modern genetics and, because of them, Mendel was hailed as the “Father of Genetics”.

But it wasn’t until 1905 that William Bateson, a proponent of Mendel’s work, coined the term “genetics” from the Greek word “genno” (meaning to “give birth”) to describe the study of inheritance and variation (Keynes & Cox, 2008).2

Fast forward to 1990, the Human Genome Project was started with the goal of sequencing and mapping the genome (collections of all the genes) of man. The project was only completed in 2003 and, for the first time, the complete genetic make-up for building a human being was shown (Moraes & Góes, 2016).3

The science may still be new, but scientists are now identifying, cataloguing, and studying small genetic variations on human genes that will (among other things) lead to more specialised and effective treatments for health and beauty.

DEMYSTIFYING GENETICS

To understand the benefits of DNA testing for variations, it’s essential to understand the fundamentals of genetics.

DNA stands for deoxyribose nucleic acid and is made up of millions of small chemicals called “bases” or “nucleotides”. There are four types of nucleotides: A, C, G and T.

A series of three-nucleotide units are known as “codons”. A combination of these four nucleotides can produce 64 codons. Of the 64 codons, 61 are code for a certain amino acid (the building blocks of protein). There are 20 amino acids which make up all the protein in our body. Some types of amino acids occur naturally in the skin and work together with aquaporins (the water transport system of your body) to transport moisture through the skin. Other amino acids work as antioxidants. Collagen is made up of 17 types of amino acids, including glycine and alanine, and is therefore recognised as beauty-enhancing, giving skin its elasticity and firmness.

Genes are segments of DNA carrying a sequence of these nucleotides or codons - the information that codes for traits or specific proteins which carry out a unique function. There are different versions of genes for each trait or protein. For example, one variant of a gene for eye colour contains instructions for blue eyes, another type contains instructions for brown eyes.

Humans have approximately 20,000 genes which are passed down from generation to generation.

Some of these genes have small sequence differences known as “polymorphisms”. A Single Nucleotide Polymorphism (SNP), pronounced ‘snip’, is the most common type of polymorphism. SNP changes at a single nucleotide make up 90% of all the variations and about three million SNPs have been identified in humans (Uthpala, et al. 2020).4

Some SNPs change the code for the gene so that either a different quantity of the protein is produced, by either increasing or decreasing the production of that protein, or the structure of the protein molecule is altered. Think of it as one letter in a word being replaced by another letter. It would effectively change the word to have a different meaning altogether.

For example, if a SNP reduces the activity of a gene that makes a vitamin A-activating enzyme, then individuals with this variation in their DNA may be at risk for low vitamin A levels. This is valuable information to have at hand, especially with the role vitamin A plays in helping to prevent breakouts or promoting natural hydration to reduce fine lines and wrinkles. In this case, incorporating treatments and supplements to support the production of vitamin Awould go a long way in slowing down the ageing process and supporting optimal skin health.

The same can be said for knowing the genes responsible for producing collagen and if there was any variation on that gene which would impact the production of the collagen in an individual. It goes without saying, treatments stimulating the production of collagen would be valuable for this individual. Collagen production is also reliant on zinc-dependent enzymes called collagenases, making testing for variations on the zinc transport gene just as important.

It is important to highlight that having a certain SNP or variation does not mean the linked outcome is certain; it merely suggests it’s more likely due to an increased risk.

NUTRIGENOMICS, NUTRIGENETICS AND DERMAGENETICS

The genome project helped scientists understand the link between genetics and health and gave new meaning to the saying “you are what you eat”.

Nutritional genetics combines the study of nutrition and genetics to discover the different ways individuals respond to food and nutrients based on their genetic makeup.

Nutrigenomics is a subfield within genomics that focuses on the influence of nutrients on gene expression and, ultimately, cellular function. Specifically, it studies how people with different genetic makeups are affected by different foods. Scientists working in the field of nutrigenomics examine how certain components and nutrients may increase the efficiency of a gene or reduce the efficiency, depending on which would lead more to the optimal health of the individual. For example, there have been studies on caffeinated coffee which show that some individuals have a particular gene that helps them metabolise caffeine faster than individuals who have the same gene but with a variation (Cornelis, et al. 2006).5

Nutrigenomics is conversely related to nutrigenetics, which studies the influence of genetics on an individual’s ability to process and respond to nutrients (Jaros, Katta & Shi, 2018).6The ultimate goal of nutrigenetics is to provide nutritional recommendations for individuals according to their genetic makeup (Uthpala, et al. 2020). 4

In 2010, Subbiah coined the term “dermagenetics,” which involves testing for select genetic variations related to skin health and recommending the use of nutraceuticals, cosmeceuticals or treatments based on the individual results (Subbiah, 2010).7

The common variations examined for skin health are related to the enzymes involved in: (a) collagen breakdown, (b) vitamin A transport, (c) vitamin C transport, and (d) zinc transport.

SO, HOW IS A GENETIC TEST PERFORMED?

A sample of cells from the inside of the cheek is collected with a swab. The whole process is painless and takes less than two minutes to complete. The DNA is extracted from the swab at the laboratory and processed. Results take on average four weeks to process.

One valid question that may spring to mind is the security of the data collected. The sample the laboratory receives is completely anonymous, so, we can all rest assured that the DNA data is completely confidential without the risk of it being shared or identified as belonging to an individual.

IN CONCLUSION

Nutrigenomics and dermagenetics have come a long way in a short time and can now be used by anyone concerned about personalising their skin care regimen, especially since genetic testing has become more affordable.

Analysing the genes responsible for collagen production, elasticity, plumpness, and the ability for the skin to utilise the nutrients you take in from your food in your DNA profile offers you unbiased, scientific recommendations on which nutrients and professional treatments your skin may benefit from.

Personalised products, nutrients and treatments are maximised by knowing your client’s genes and scientifically identifying what works for their DNA.

Becoming more informed allows you to be in control of your client’s health and well-being, and that includes their skin’s health. You can offer a truly unique service by including the final piece of the jigsaw - genetics.

KAREN HARRISON MSc, mAfN, mBANT, rCNHC.

Owner of Team Gene Skin Completed >7,000 hours in clinical practice or supervising students. Spent more than 10 years in the nutrition and genetics industry. Karen is one of 45 alumni from St Mary’s University with a MSc in Nutrition and Genetics and BSc in nutritional science from CNELM.