LONDON: In his famous Two Cultures lecture, CP Snow lamented the deep divide that separates the arts and humanities in modern culture. But recent work published in Genome Biology by researchers Rie Takahashi and Jeffrey H Miller at the University of California, Los Angeles (UCLA), might be a step towards healing the rift. The scientists designed a computer programme that turns genes into music. The resulting tunes are surprisingly melodic and have a curious resonance with the roots of both western music and science 26 centuries ago.

Takahashi and Miller’s approach is not entirely new. In 1986, Ohno and Ohno transposed DNA sequences into musical notes, but the four letters of the genetic code (the DNA bases A, T, G and C) provided only very limited musical range. Takahashi and Miller turned to the proteins (encoded by the DNA genes). Since they are composed of 20 different amino acids they were initially each allocated a note on the 12-note chromatic scale (all the notes in the same octave), but the compositions tended to jump sporadically from one note to another and lacked melody.

So Takahashi and Miller reduced the number of possible notes by assigning pairs of similar amino acids to a single note in the seven-note diatonic (the familiar doh, ray, me) scale. But instead of employing a simple amino acid to musical note transposition, the molecular musicologists allowed the amino acids to encode three-note chords. For instance, the amino acids tyrosine and phenylalanine were both assigned a G major chord but were distinguished by tyrosine being given the G major root position chord whereas phenylalanine was transposed into a G major first inversion chord.The use of chords made the genetic compositions flow more smoothly and provided emotional depth (“how strange, the change, from major to minor”). But it still ain’t got rhythm. To inject the rhythm, they used the frequency of the DNA code that specified each amino acid to assign a time period to each note.

For their first composition the researchers transposed the thymidylate synthase A protein (involved in making DNA) into a pleasant little melody. Their next piece was a segment of the protein that causes the disease Huntington’s chorea. The Huntington gene provided a more sombre tune that was interrupted by a repetitive beat denoting a string of glutamines. Genetic mutations lengthen the repetitive regions in the gene until they eventually become pathological, and would be heard as an increasingly monotonous beat.

The research has interesting parallels with the condition known as synaesthesia, in which sensory perceptions get mixed up. Synaesthetes may perceive a colour when they hear a musical note, or experience a smell when they see a colour. The condition is often associated with creative talents, but, though the full-blown condition is rare, most people associate low musical notes with dark colours and high notes with lighter colours. Takahashi and Miller’s programme performs a synaesthesia-like mapping of genetic information into auditory information. It is possible that the ear may provide a more efficient means of analysing genetic information and spotting certain types of mutations.

Takahashi and Miller’s plucking of protein strings to make music also has ancient resonance with the plucking of harp strings to make science 26 centuries ago. Pythagoras of Samos discovered that if a string was plucked and then cut to half its length and plucked again, the difference in pitch between the first and second note would be an octave. So an octave has a numerical ratio of 2:1. He discovered similar simple ratios for all the principle harmonies. This discovery of a connection between number and harmony became the central theme of Pythagorean philosophy and, through followers such as Plato, had a huge influence on the development of western philosophy. It was further developed by Greek mathematicians, such as Euclid, to eventually become the cornerstone of western science.

It’s nearly 50 years since CP Snow delivered his famous lecture, but the arts and sciences are as far apart as ever. Takahashi and Miller’s transposition of science into music repays an ancient debt; but perhaps also reminds us that the complementary disciplines have a common root, and once shared the same interests.—Dawn/The Guardian News Service