Two sequencing techniques were developed independently in the
1970s. The method developed by Fred Sanger used chemically
altered "dideoxy" bases to terminate newly synthesized DNA
fragments at specific bases (either A, C, T, or G). These
fragments are then size-separated, and the DNA sequence can be
read. fred sanger,dna fragments,dna sequencing,dna
sequence,1970s The sequencing method developed by Fred Sanger
forms the basis of automated "cycle" sequencing reactions today.
Fluorescent dyes are added to the reactions, and a laser within
an automated DNA sequencing machine is used to analyze the DNA
fragments produc Techniques to read the sequence of DNA, letter
by letter, have been available since the 1970s. However, the
massive task of sequencing the three billion basepairs of the
human genome required machines that could read and interpret the
data.