Friday Grand Rounds: Russ Altman Introduces Pharmacogenomics Database PharmGKB

Every human cell, with two sets of 23 chromosomes, contains six-billion basepairs of DNA (or three-billion per haploid genome).  Of these three-billion genomic basepairs, each individual shares 99.7% with the rest of the humanity.  It is the three-tenths of a percent that determines the differences between all of us.  This tiny percent, nevertheless, comprises of about a million positions that not only make us unique individuals, but also determine how we respond to environment, succumb to certain diseases, or respond (or not) to certain drugs.  These single nucleotide changes, scattered all over the genome, are called single-nucleotide polymorphism (SNP, pronounced snip) - for example, I may have Adenine at position X, you may have C and my friend may have G at the same position.  Since the complete sequencing of human genome in 2003, the post-genomic goal has been, to answer how this 0.3% of genome determines phenotype.  Pharmacogenomics/Pharmacogenetics (PGx) is the study of how genetic makeup correlates to responses to various drugs.