Here is something to ponder. Things are seldom what they seem.
What percentage of human DNA is shared with other things?
6 Answers

Xu Beixi, loves Nature.
Answered Mar 24 2014 · Author has 4.7k answers and 31.1m answer views
It depends on what you mean by share.
What do you consider the premise of your study? It it genome size, number of genes, chromosome number, phylogeny, etc. etc.? What constitutes alike as to different?
Also, it doesn't help that we don't know what all our genes are for, how they're used, what proteins they make, and there are so many ways for post-transcriptional modification that we can't begin to figure all of them out.
Finally, to answer:
It is very difficult to find reliable data
comparing the human genome to animal genome. The principal reason is that few animals have had their full genome sequenced. Even those that have cannot be easily compared in terms of percentages because the genomic length and chromosomal division can vary greatly from one species to another.
Scouring the Web, here is what I have found so far.
- Genome-wide variation from one
human being to another can be up to 0.5% (99.5% similarity)
-
Chimpanzees are 96% to 98% similar to humans, depending on how it is calculated.
-
Cats have 90% of homologous genes with humans, 82% with dogs, 80% with cows, 79% with chimpanzees, 69% with rats and 67% with mice.
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Cows (
Bos taurus) are 80% genetically similar to humans
- 75% of
mouse genes have equivalents in humans (
source), 90% of the mouse genome could be lined up with a region on the human genome 99% of mouse genes turn out to have analogues in humans
- The
fruit fly (
Drosophila) shares about 60% of its DNA with humans.
- About 60% of
chicken genes correspond to a similar human gene.