University of Texas

Bardet-Biedl syndrome and Meckel-Gruber syndrome are seemingly related to each other. These two disorders have not been studied well and are believed to result in mental retardation, obesity, blindness and kidney failure. A latest research triggered by the University of Texas and Duke University reveals gene mutations called ‘Fritz’ to cause human genetic disorders like Bardet-Biedl syndrome.

Claimed to be a novel research, scientists have shed light on Fritz’s possible role in human disorders. The gene is believed to play a major role in two processes involved in the development of embryos. The first process may include the collective movement of cells as they mold the shape of developing embryos. And secondly, the creation of cilia, projections from cells that serve as sensory antennae. On regulating the septins molecules, Fritz gene is possibly able to control these processes.

“Normally, movement of the cell membrane is smooth in developing embryo. But those embryos without Fritz had cell membranes that were waving and jostling around. Septins basically make a coat across the plasma membrane and stabilize it. Because the membranes looked floppy, the septins are one of the things we looked at,” elucidated John Wallingford associate professor of biology.

Structural support to cell membranes is assumed to be given by septins. The scientists visualized time-lapse videos of developing frog embryos with and without the gene. These videos seemingly empowered experts to understand the role of Fritz in regulating septins. In the course of investigations, scientists demonstrated Fritz gene deficiency in various ways in the developing embryo.

Nicholas Katsanis human geneticist and cell biologist from Duke University affirmed, “This result obviously furthers our understanding of these syndromes. Perhaps more important, however, we now have both hard evidence for previous suspicions and a brand new set of mechanistic underpinning for ciliary dysfunction in people”.

Embryos in the beginning stages seemingly revealed difficulties in collective cell movement and growing longer. So various morphological problems, like defects in the neural tube can be possibly triggered. In the later stages, embryos displayed cranio-facial malformations very much alike those viewed in patients suffering from Meckel-Gruber. The experts suggest malfunctions in cilia to be the cause of such deformities.

Wallingford quoted, “This is a good example of studying basic cellular biology that leads to insights in human diseases. If we just think about the way basic biology links in with humans, there’s the ability to make that leap. We will discover things about human diseases even when we are trying to study frog development.”

It was therefore concluded that septins can be redistributed in various ways in these varied cell types. Having scrutinized data provided by the Wallingford lab, experts found patients with Bardet-Biedl and Meckel-Gruber syndromes to have mutations in the Fritz gene. The findings also suggest the mechanisms that help in controlling fundamental cellular machinery during embryonic development. These mechanisms are claimed to be associated to human disease.

The research is published online in Science Express.