Using sequence data to test hypotheses: Influenza viruses

Abstract

The sequences of macromolecules contain information about the h is to ry of organisms, though i t is d i f f i c u l t to use th is informat ion in a quant i ta t ive manner. We have used hemeagglutinen and neuraminidase sequences from inf luenza viruses in order to test the theories of Hoyle and Wickramasinghe. Three main versions of the i r models have been tested. The f i r s t version was that the sequences evolved independently from a common ancestor, but on d i f f e ren t comets. Testing th is model required being able to predic t the expected lengths of minimal trees from sequence data. The length of the actual minimal tree is far too short to have arisen by th is independent model; with nine hemagglutinen sequences the minimal t ree would be found only once in every lx10 -75 t r i a l s .