Rutgers researcher offers a new perspective on human evolution

The fossil remains of early humans gave generations of scientists the clues needed to piece together much of our ancestral lineage. Chi-Hua Chiu now leads us into another dimension in the study of human origins: the underlying developmental and genetic processes that led to these remarkable evolutionary changes.

“To develop a better understanding of the genetic basis of human evolution, we must discover specific relationships between particular genetic changes and their resulting effects on the body plan,” said Chiu, an assistant professor of genetics and anthropology at Rutgers, The State University of New Jersey.

Chiu explained that our expanding knowledge of genomics will open doors to an understanding of the ways in which genes regulate development, both in humans and their nonhuman relations.

Locomotion and limb structure have long been topics of interest to paleoanthropologists. In a presentation at the annual meeting of the American Association for the Advancement of Science in Seattle Monday (Feb. 16), Chiu spoke of correlating the evolution of genes responsible for the formation of arms and legs with the observable diversity in limb structure among humans and other primates.

In the growing field of evolution and development, known as EvoDevo, the view is that significant developmental differences are due to changes in gene regulation. “Once we have the structure of gene regulatory sequences, comparative studies of humans and nonhuman primates can be used to examine the evolution of these sequences, their functions and the resulting anatomical differences,” said Chiu.

Chiu counseled her listeners to look to the mouse for answers, as have many research scientists before. “Primates are not ideal model organisms for developmental genetics and embryology because they have long generation times and produce small litters,” she said.

Recognizing that mice certainly have important limitations as models for human or nonhuman primate development, Chiu noted that historical uses of mice in the laboratory have given EvoDevo researchers a head start. “There is already a substantial amount of information available on mouse developmental genetics,” she said.

“Modern developmental genetics, comparative genomics and molecular embryology with model organisms provide the foundation on which to build innovative studies of genotype-phenotype relationships in human origins.”