How do genes influence behavior? Abraham Palmer, AB’92, PhD A S S O C I AT E P R O F E S S O R
HUMAN GENETICS
PHOTO BY ROBERT KOZLOFF
that are partially genetic lead to different behaviors and different ways of relating to the world.” While a sample size of 10,000 is an impressive number, it is still too small to identify specific genes for complex and variable behavioral traits. To draw unambiguous links, study sizes of 25,000, 50,000 and upward are needed. Only a few short years ago, this would have been unthinkable. But innovations in the field of human genetics are spawning genetic profiling technologies that are rapidly increasing in power and decreasing in cost. Taking advantage of this trend, Palmer is engaging in a unique partnership with 23andMe, a Californiabased company that offers genetic tests for ancestry for less than $100. With the voluntary participation of 23andMe customers, Palmer and his collaborators are sending carefully designed questionnaires to identify individuals with behavioral traits including loneliness. Since they have known genetic profiles, this represents an opportunity to add potentially tens of thousands more samples to the UChicago researchers’ studies. “A partnership with a company like 23andMe was uchospitals.edu/midway
not something you could imagine 10 years ago,” Palmer said. “There’s really an opportunity now, with all these technologies available, to start unlocking, at the molecular level, questions that we couldn’t even have hoped to have framed.” Studies of this kind are not simply for the sake of new knowledge. Loneliness is not a disease, but it is correlated with increased risk of depression, neurovascular issues and even death. Other behaviors that Palmer studies with close collaborators at the University of Chicago and around the world are closely tied to human health as well. They include impulsivity, which is linked to increased risk for drug abuse. To understand how these genes function and to make potential use of them to treat disease, Palmer and his colleagues utilize tools to overexpress or delete the genes in mice and rats, and to measure the subsequent effects on behavior. This has proven a fruitful approach. While studying anxiety, they found that mice that overexpressed the gene Glo1 had more anxiety-like behavior. This was strange because Glo1 — a gene involved in sugar metabolism that can be found in both plants and MEDICINE ON THE MIDWAY
SPRING 2015
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