Scientists Spot Common Vertebrate/Insect Gene

Harvard scientists recently helped identify a gene fragment common to both vertebrates and insects which may be the key step in solving some of genetics' most puzzling processes.

The discovery shows a common gene fragment in flies, earthworms, chickens, frogs, and humans, which may improve the understanding of developmental processes including birth defects.

Reported in the latest issue of Nature magazine, the unexpected finding marks a major breakthrough in understanding vertebrate development, said Professor of Biochemistry Gary Struhl.

Human-Insect Link

The common fragment's identification--discovered through an international effort concentrated in the United States and Switzerland "shows that we are a lot closer to insects than we think, although this may offend some people, said William M. Gelbart, professor of Biology.


The results raise the interesting possibility that insects have analogs to vertebrates, he added.

Because the discovery shows similar underlying mechanisms in all genes, it may have implications for comparing developmental processes between humans and insects.

A variety of human birth defects presumably have their origins in failures of the genetic control of embryonic development.

In the closely studied fruit fly, the gene fragment appears in genes which control the insects' physical structure. When the genes are damaged, defects such as feet attached at the wrong end of the insect result.

According to the Nature article written by Struhl, the occurrence of a similar fragment in vertebrates could play a role in tracing human develompment, materializing general principles may govern both insect and vertebrate development.

A Harvard Medical School team, led by Assistant Professor in Biological Chemistry Welcome W. responsible for cloning a biothorax which lead to the discovery. Scientists later compared this to production of the DNA by researchers in Colorado.

The finding stemmied from a careful watching of the genetic development of various insect parts, such us the thorax or abdomen. Alteration of some genes causes legs or thorax segments to develop where the abdomen should be, for exmaple.

Each segment seems alike at development's earliest stage and contains the genetic information to make any one of the adult parts: said Allen Laughon of the University of Colorado, where much of the research took place.

Then a gene "tells" each seemingly identical segment how to develop.

In human beings, segmentation is less obvious, but does occur in body parts such as the ribs and spinal ganglia of the central nervous system