Washington, November 15: University of Toronto researchers have moved one step further towards understanding why humans differ so greatly from chimpanzees in terms of looks, behaviour and disease immunity when 99 per cent of their genes are similar.

Professor Benjamin Blencowe and his colleagues compared brain and heart tissue from humans and chimpanzees.

The study enabled them to notice significant differences in the way the coding regions of their genes are linked to generate genetic messages that specify the production of proteins, the key structural and functional constituents of cells.

The process by which the coding regions of genes are joined to generate genetic messages is called splicing.

“It’s clear that humans are very different from chimpanzees on several levels, but we wanted to find out if it could be the splicing process that accounts for some of these fundamental differences, ” he says.

“The surprising thing we found was that six to eight per cent of the alternative splicing events we looked at were showing differences, which is quite significant. And those genes that showed differences in splicing are associated with a range of important processes, including susceptibility to certain diseases, ” he adds.

According to the researchers, splicing can occur in alternative ways in the same genetic message to generate more than one type of protein. They say that the alternative splicing process differs significantly between humans and chimpanzees.

Blencowe believes that the new finding may have implications for the future study of disease in humans and chimpanzees.

“Identifying what makes us different can be very important to understanding why certain diseases affect one species and not the other, ” he says.

The study has been published in the Journal of Genes and Development. (ANI)