One was the genetic definition of the gene, which is the unit of function. And any gene sequence that makes a protein with a different function is by definition a different gene. But, when you have a DNA sequence that can give rise to different proteins through alternative splicing or by other mechanisms, the DNA sequence, in the genetic view of things, can be thought of as providing multiple different units of function. Now, that will be closer to the 70,000 to 100,000 genes that were originally estimated. And, there also seems to be a crisis of complexity if you read the popular press, with much hand-wringing over how we could only have twice an many genes as a simple worm.
People worry that the human genome is too simple.
But few things in biology are ever done by a single protein acting alone. Inc. All rights reserved.