The area of the human genome that is contained within genes is a fraction of the total DNA. Genes themselves are comprised of promoters, enhancers, upstream and downstream regulatory sequences, coding and non-coding sections of the message. The coding parts, that are the blueprint for the proteins or RNAs, are themselves small parts of the entire gene.
I'm not sure if the researchers here are using the word "gene" in the context of the entire gene with all the regulatory sequences included, or just the part of the gene that codes for a product (which is also a correct use of the word).
Either way, when the researchers state that 7 percent of the genes are undergoing rapid evolution, they are talking about a very small fraction of the entire human genome.
So, the 7 per cent figure is the fraction of the 1 per cent figure that is not totally identical?