Cytogenetics is the field genetics at a cellular level, which means looking at chromosomes (bundles of DNA). Clinical Cytogeneticist, Charlotte Keith, discusses the areas of testing; acquired and constitutional, which is broken down into prenatal and postnatal. She explains how balanced and unbalanced rearrangements work and talks about a case that explains the concept. Charlotte gives us an UK view of how genetic counseling is incorporated into their genetic testing process and just how complex “informed consent” is when it comes to genetic testing as incidental findings do happen. Direct-to-consumer testing becoming more popular and Charlotte adds in her opinion on these companies and the science behind them. Check out the website Charlotte recommends for understanding chromosome disorders, http://www.rarechromo.org, it has resources for countless syndromes with downloadable pdfs outlining information in laymen’s terms. She also mentions the Deciphering Developmental Disorders (DDD) project and the 100,000 Genomes Project. Charlotte Keith is a Clinical Cytogeneticist from Edinburgh, Scotland. She works for the South East Scotland Genetics Service, providing diagnostic and prognostic genetic testing for NHS (National Health Service) patients.