This case study is designed to teach basic concepts of genetics by focusing on a rare disease, pseudoxanthoma elasticum (PXE).  Chromosome 16 is the narrator at the beginning of the case and introduces students to genes, chromosomes and mutations. The focus then shifts to the patient and his mother as she finds out about her son’s disease and her subsequent efforts to connect with patient advocacy groups for support. The case concludes with students watching a TED talk given by Sharon Terry, the real-life mother on whom this story is loosely based, so that students can connect on an emotional and human level with someone who has intimate experience as a parent of children with a rare genetic disease. The case is suitable for high school general biology classes, but it can also be used by biology major or non-major undergraduates in a lower-division biology class, or in any lower-division non-major class focused on human disease.