If you've ever read a pharmacogenomic (PGx) report and wondered why one finding appears as "CYP2C19 *2" in one place, "rs4244285" in another and "c.681G>A" in a third, you're not alone. Three terms come up constantly: SNP, mutation, and star allele. They overlap, they're often used interchangeably, and they describe genetic information at different levels. What is a SNP? A single nucleotide polymorphism (SNP) is a spot in the genome where a single DNA letter differs between p

Most of us glance at our blood group on a hospital form — A, B, AB, or O, plus or minus — and think nothing more of it. But that little label is actually a fossil record. It tells a story of ancient plagues, small bands of migrating humans, and one of the strangest genetic detective stories in medicine. First, what is a blood "type" really? Your red blood cells are covered in tiny sugar molecules called antigens, sitting on the cell surface like flags. The ABO system depends

If you have ever been told you have polycystic ovary syndrome — or if you suspect you might — you may already know the frustration of a name that doesn’t quite fit. Maybe you were told you have “cysts on your ovaries,” only to discover on further examination that you don’t have classic cysts at all. Maybe your primary complaint was fatigue, weight gain, or a skin condition, and yet the conversation kept circling back to your fertility. You were not imagining the disconnect. T