What is personal genomics

UZH News

Weizmann Lecture

Personalized medicine aims to tailor the prevention, diagnosis and therapy of diseases on the basis of individual genetic analyzes. At the Weizmann Lecture, prominent scientists provided insights into the current state of research.

Michael Keller

"The entire genome of a person can be sequenced within two days," said Professor Martin E. Schwab, neurobiologist. (Image: Michael Keller)

Significant developments in research often go hand in hand with big leaps in technology. "In the case of personalized medicine, this is the technical progress in genome sequencing, which enables an exact analysis of the approximately 30,000 genes in our genetic material," said Martin E. Schwab, Professor of Brain Research at the University and ETH Zurich, introductory to the symposium. In fact, gene sequencing - a very expensive technique until a few years ago - has become around a thousand times faster and a million times cheaper since the human genome project. "Today, the entire genome of a person can be sequenced within two days for CHF 2,000," says Schwab.

Personal genome encyclopedias

Doron Lancet, human genomist at the Weizmann Institute of Science in Israel, spoke of a real revolution. In his historical review he pointed out that in the human genome project fragments from the genome of different people were mixed up. Today, however, basically every person could have their own, individual genome encyclopedia created. On the basis of such personal gene data sets, errors in the genome can be diagnosed at an early stage, which works particularly well in the so-called monogenic diseases, which are caused by a defect in a single gene, he explained.

Speaking of the human genome project as a real revolution: Doron Lancet, Professor of Human Genomics at the Weizmann Institute. (Image: Michael Keller)

As an example of what personalized medicine can mean, the Lancet cited sudden cardiac death in young people. His group had deciphered the responsible gene and its mutation. «The knowledge is used today for diagnostic genetic tests. Medication is also available so that death can be effectively prevented, provided that one knows about the predisposition, ”says the researcher.

Most known diseases, however, are polygenic in nature, i.e. based on a combination of several gene variants and mutations. Schizophrenia, for example. "The genetic decoding of such complex clinical pictures is a huge undertaking - we are only at the beginning," emphasized Lancet. But with globally united forces and with the necessary technology, research will find all the fine needles in the genomic haystack in the next few years, he assured us.

Personalization of memory

Andreas Papassotiropoulos, Director of the Department of Molecular Neurosciences at the Faculty of Psychology at the University of Basel, shed light on the subject of personalized medicine from the perspective of brain research. His area of ​​expertise covers the molecular basis of human memory: "Human genetics is important for the identification of memory-relevant genes and their protein molecules," he explained, "it is important not to draw false conclusions."

Warned against drawing conclusions from the group about the individual: Andreas Papassotiropoulos, neuroscientist at the University of Basel. (Image: Michael Keller)

Papassotiropoulos illustrated what he meant by using the gene for the serotonin receptor as an example. There are two variants of this gene. The corresponding proteins differ at a certain point in the blueprint by the respective building blocks «tyrosine» and «histidine». "If you divide people into two groups according to this criterion and test them for their memory performance, it clearly shows that the group with the tyrosine variant performs worse on average," said Papassotiropoulos and pointed out that other variations of Genes existed that revealed similar differences in performance in group studies.

“This shows us that the genes we are looking at have an effective effect on memory performance. But what does that mean for the individual carrier of the tyrosine variant - does he consequently have a bad memory? ”Asked the researcher. By no means was the answer. Group comparisons, however significant they are, only allowed statements about the group, but no conclusions about the individual. This is a common misinterpretation in connection with personalized medicine, he summed up. "You don't need a genome analysis to find out whether you have a good memory - you can easily test it yourself," said the researcher with a smile.

The Weizman Lecture is organized every year at the University of Zurich by the Society of Swiss Friends of the Weizmann Institute of Science. The Weizmann Institute of Science in Rehovot, Israel was founded by the chemist and first President of Israel, Chaim Weizmann, in 1934. Today it comprises 17 departments in the five faculties of biology, biochemistry, chemistry, physics and mathematics and employs around 2,600 people.

Michael Keller is a freelance science journalist.