Scientists discovered that many of the genetic diseases humans have came from early species in the evolutionary chain, approximately 400 million years ago. Bacteria are most responsible for afflictions such as diabetes and Huntington's disease, with more than 97 percent of our current susceptibilities to infections deriving from their gene pool. This means that geneticists will soon be able to extend their studies on fish and birds as well, giving the poor mice a well-deserved break.

 

Specialists have known for a long time that well over 40 percent of our genes directly descend from bacteria. That is to say, it's obvious our evolutionary path left theirs when the first fish "stepped" out of the water. Nevertheless, more than 60 percent of all disease genes that humans currently have in their genomes come directly from bacteria. That could be a reason why bacterial infections such as tuberculosis are so old and difficult, if not impossible, to treat or cure.

 

More than 400 million years ago, the early forms of humans had already encountered over 98 percent of the diseases we are faced with so many years later. According to recent studies, only 0.45 percent of the disease genes we currently have came from mammals, later on in the evolutionary path, some 250 million years ago.

 

Given these facts, geneticists concluded that parallels between humans, fish and birds could be easily drawn, now that they know what to look for. Further advancements in microbiology and genetics could be possible at a much higher rate than at present, when mice are the main test subjects researchers use, as they have a very close genome composition to our own.

 

Another positive aspect about this find is that working with simpler organisms than mice can give scientists the possibility to genetically manipulate the subjects more quickly and thus determine the efficiency of a treatment, therapy or cure faster than they do now.