In this explainer episode, we’ve asked Dr Nour Elkhateeb, clinical fellow at Genomics England and clinical geneticist for the NHS, to explain the role of a clinical geneticist. The previous episode mentioned in the conversation is linked below. What is the diagnostic odyssey? You can also find a series of short videos explaining some of the common terms you might encounter about genomics on our YouTube channel. If you’ve got any questions, or have any other topics you’d like us to explain, let us know on podcast@genomicsengland.co.uk. You can download the transcript or read it below. Florence: What is a clinical geneticist? My name is Florence Cornish and I'm here with Nour Elkhateeb, clinical geneticist for the NHS and fellow at Genomics England, to find out more. So, Nour, before we dive into talking about clinical geneticists, could you explain what we mean by the term genetics? Nour: Hi Florence, so at its heart, genetics is the study of our genes and how they are passed down through families. Think of your genome as a huge, incredibly detailed instruction manual for building and running your body. This manual is written in a specific language, DNA, which is made up of millions of letters arranged in a specific order.  And here is the interesting part, we all have tiny differences in our genetic spelling, which is what makes each of us unique.  But sometimes a change in the instructions, a spelling mistake in a critical place, can affect health. Genetics is all about learning to read that manual, understand how changes in it can cause disease, how it's passed down through families and finding ways to help.   Florence: And so, what kind of thing does a geneticist actually do? Nour: Well, the term geneticist can cover a few different roles, which often work together. Crudely speaking, you can think of two main types, laboratory geneticists and clinical geneticists.   Laboratory geneticists are the incredible scientists who work behind the scenes. When we send a blood sample for genomic sequencing, they are the ones who use amazing technology to read the billions of letters in that person's instruction manual. The job is to find the one tiny spelling mistake among those billions of letters that might be causing a health problem.  Clinical geneticists like me are medical doctors specialised in the field of genetics, and we work face-to-face with patients and families in a hospital or a clinic setting. You can think of us as the bridge between the incredibly complex science of the genomics lab and the real-life health journey of the person in front of them. We diagnose, manage and provide support for individuals and families who are affected by or at risk of genetic conditions. And we translate that complex genetic information into meaningful information for the patient, the family and the other doctors as well.  Florence: So, let's talk a little bit more about clinical geneticists. What stage of someone's genomics journey are they likely to see you? What are some typical reasons they might get referred, for example?  Nour: That's a really good question. So, people actually can be seen by clinical geneticists at almost any stage of life, and for many different reasons. Let me give you some examples.  We see a lot of babies and children. A family may be referred to us if their baby is born with health problems that do not have a clear cause, or if a child is not developing as expected. And sometimes families may have been searching for answers for years, or what we call a diagnostic odyssey, but no one has been able to find a single unifying diagnosis to explain their challenges. And our job is to see if there is a genetic explanation that can connect all the dots.  Florence: You touched there on the diagnostic odyssey, and I know we don't have time to dive into that right now, but if listeners want to learn more about this, then they can check out our previous Genomics 101 podcast: What is the Diagnostic Odyssey?