Modern medicine has hardly advanced since the butchery of Victorian times, according to Peter Goodfellow, a leading geneticist at SmithKline Beecham's pharmaceuticals research centre at Harlow in Essex. What we're talking about is the genetic master plan for assembling and maintaining a human being. All our cells, except red blood cells, carry copies of the master plan. There are 24 different chapters, or chromosomes. Girls inherit an X chromosome from each parent, whereas boys receive an X from their mother and a Y from their father.
Faulty genes can cause disease.
The haemophilia which cursed Europe's royal families, for example, was caused by a defective gene which messes up the manufacture of a key blood-clotting protein. By decoding the genome scientists expect to discover exactly how genetic misprints cause disease. It should then be possible to produce a drug or therapy to compensate, just as insulin is given to diabetics and clotting factor to haemophiliacs. Finding the gene is just the first step. The roots of diseases like haemophilia, which result from a single faulty gene, are relatively easy to spot by studying family medical histories.