The cost to decode the entirety of someone’s genes has dropped dramatically, paving the way for improved disease surveillance. The lower cost has made this technology accessible for people living in poorer economies giving hope that emerging diseases will be spotted and characterised sooner.
The human body is an information keeper. Each of our 30 trillion cells, give or take, keeps information on how body machinery works and passes the information to the next generation in strings of code using only four letters, ACGT. Each stands for a type of molecule called nucleotide. The string has a total length of around 6 billion letters, condensed into 23 pairs of chromosomes that make up the DNA.
Seventy years ago, James Watson and Francis Crick discovered the shape of DNA and how the ACGT code fitted together. All living things are identifiable by reading their DNA code, or in some organisms their RNA, known as their genome. In the 1970s Frederick Sanger developed a method, known as sequencing, to read that code. The first reading of a human’s DNA was laborious; it took around 10 years to read the majority of the three billion letters.
