Man, if I had a dollar for every time somebody told me that the fusion site doesn’t look like what we would expect it to look like, I’d have twenty-something million dollars. So, I thought I might download some DNA sequences for known mammalian fusions and show you what they look like.
Now the sequences I’m about to show you are from the Indian muntjac species, and if I may quote from a paper published in 2008:
Indian muntjac (Muntiacus muntjak vaginalis) has an extreme mammalian karyotype, with only six and seven chromosomes in the female and male, respectively. Chinese muntjac (Muntiacus reevesi) has a more typical mammalian karyotype, with 46 chromosomes in both sexes.
So clearly there have been a bunch of fusions in this Indian muntjac species and – luckily for us – they decided to sequence these fusion sites to see what they looked like. Now, remember these are not telomere-to-telomere fusions, these are telomere-to-satellite fusions, so they only correspond to one side of the human chromosome 2 fusion site.
“In chromosome fusion events that occur in nature in living mammals—a very rare event—the DNA signature always involves satDNA producing a DNA signature that occurs as either satDNA-satDNA or satDNA-teloDNA sequence.”
Behold!
This is what fusions actually look like.
http://www.ncbi.nlm.nih.gov/nuccore/DP000824
AGAGATCTAGTTTTCCACCAAAGATTTAAAATATCTCTCTGACCTCCTTTTTTTTGGGGAGGGGGGGGAG GGTTTGAAGTTTTCATTTGCCCAAGGTTGAGGTCTCAGGCAAAGTAGGCAGTGTTTTCAAGGAAAGGGTT CGGGTTCGGGTTCGGGTTCGGGTTCGGGTTCGGGTTAGGGTTCGGGTTAGGGTTAGGGTTCAGGTTAGGG TTAGGGTTCGGGTTAGGGTTCGGGTTAGGGTTCGGGTTTAGGGTTAGGGTTCGGGTTAGGGTTAGGGGTT AGGGTTAGGGATAGGGTTAGGGTTAGGGTTAGGGGTTAGGGTTCGGGTTAGGGTTAGGGTTCGGGTTAGG TTTGGGGTTAGGGTTAGGGTTAGGGGTTAGGGTTAGGGTTAGGTTTAGGGTTTAGGGTTAGGGTTACGGT TAGGGTTAGGGTTAGGGTTAGGGTTTAGGGTTAGTGTTAGGGTTAGGGTTAGGGTCAGGGTTAGGGTTTA GGGTTAGGGTTAGGGTTAGGGTTAGGGTTTAGGGTTAGGGTTTAGGGTTAGGGTTAGGGTTAGGGTTAGG GTTAGGGGTTAGGGTTAGGGTTAGGGTTAGGGATTAGGGTTAGGGTTAGGGTTAGGGTTAGGGTTAGGGT GATAAGGCATTCTCTAGTGTCTCCCCAGGGGCTTCAGACTTCCCTTCATCTTGTGACACGTAATCCAGCT TGTACTCAAGTCAGTGCAGGAATTCCGGCCTGATTTCCAGTCAGGGCATTTCAGGGTCGATTCCACTGGA
http://www.ncbi.nlm.nih.gov/nuccore/DP000825
TAGAATATCATGGCCATCAAACGTCGGGTCATCTTTCTTTCCTGATGGCATAGTTTTACCGCTGAATTAT ACACAGATCAGCTGACAAGGTGATGTGAACCTGCGGAAGGAAGGATCACTAACGTGGTTCGGGAAAGGGG TTTGGGTTCGGGTTCGGGTTCGGGTTCGGGTTCGGGTTCGGGTTAGGGTTCGGGTTAGGGTTAGGGTTAG GGTTAGGGTTTGGGTTTGGGTTAGGGTTAGGGTTCGGGTTCGGGTTAGGGTTAGGGTTCGGGTTAGGGTT CGGGTTAGGGTTTAGGGTTAGGGTTAGGGTTAGGGTTAGGGTTCGGGTTCGGGTTCAGGTTAGGGTTAGG GTTAGGGTTAGCGGTTAGGGTTAGGGTTAGGGTTAGGGTTAGGGGTTAGTGTTAGGGTTAGGGTTAGGCT TAGGGTTTAGGGTTAGGGTTAGGGTTAGGGTTAGGGTCAGGGTTTAGGGTTAGGGTTAGGGTTAGGGTTA GGGTTTAGGGTTTAGGGTTTAGGGTTTAGGGGTTAGGGTTAGGGTAAGGTTTAGGGTTAGGGGTTAGGGT TAGGGTTAGCGTTAGGGTTAGGGTTAGGGTTAGGGGTTAGGGTAGGGTTCGGGTTAGGGTTAGGGTTAGG GTTAGGTTTCGGGTTAGGGTTCGGCTTAGGGTTCGGGTTAGGGTTTAGGGTTAGGGTTTAGGGTTAGGGT TAGGGTTAGGGTTCGGGTTCGGGTTAGGGTTAGGGTTAGGGTTAGGGTTAGGGTTAGGCTCCTTTCAAGT TTGATTGCGAGCACGGAATTGCTCTGCACGCAGTGCAGGGGAATCGGGCCTCATCTCATGGTGAGGGGGA AGTCTCATGGTTTTTCTCGAGTTGCGGCCGGAACCTGGGATATATTCTCGAGTTACGACAGGGATGGCCC
http://www.ncbi.nlm.nih.gov/nuccore/DP000826
CTAGGTCAGGTCATCTTTCCTTTCTGTAGTCATAGTTAGACAGATCAGCTGATAAAAACCTTGGATTGTG TCTGTGGGGTGGATTTGCTTGTCATTGTGCTTCAGCTGGCCAAGGTAGCAACGCCCGCGCCCCTCCCACG GAAGTAGGAGTGGGGGCGGGGCGCACCGGGGGAGTGTCGGGCCGGGTTAGGGCTAGGGCTTAGGGCTTAG GGCTTAGGGCTTAGGGCTTAGGGCTGAGGTTGGGGTTAAGGCTTAGGGTTAGGGCTGGGGTTGGGGTTAG GGCTTAGGGCTTAGGGCTAGGGTTAGGGTTGGGCTTAGGGCTAGGGTTAGGGCTTAGGGCTTAGGGCTAG GGCTTAGGGCTAGGGTTAGGGGTTAGGGTTAGGGTTAGGGTTAGAGGGTTAGGGTTAGGGTTAGGGTTAG GGTTAGGGGTTAGGGTTAGGGTTAGGGTTAGGGTTACGGTTAGCGTTAGGGTTAGGGTTAGGGGTTAGGG TTAGGGTTAGGGTTAGGGTTACGGTTAGCGTTAGGGTTAGGGTTAGGGTTAGGGTTAGGGTTTAGGGTTA GGGTTAGGTTTAGGGTTAGGGTTTAGGGTTAGGGTTAGGGTTAGTGTTAGGGTTAGGGTCTGGATTGTCT CCAGAGCCATCCCGCCTTCCCCATCAAACATGACAAGTGGCTTGACTTCCTTTAGACAGTTCCGAAGATT CCTCGAGAATATCGTCGTCACAAGTCTAGAGGAACACCAAGTTCAGCACAGCAACTCGAGAAAAGCTCCG
http://www.ncbi.nlm.nih.gov/nuccore/DP000827
CTAGCTACCAGTCATTTAGAATAATTTACTGGATGCCGTCAACCACATTCTGTTTAGAGTGTACATATGC AAATTGAATACAAGAAAAAAAAAACAACGAAACAGAACCCACTCATCTGGTTTTAAACCAAGATCATAAT CACTATATCTTTCTCAATATATGAGATGTTAGTGAAAAATAATGTTAGGGTTAGGGGTTAGGGTTAGGGT TAGGGTTGGGGTTGGGGTTAGGGTTAGGGTTAGGGTTAGGGTTCGGGGTTAGGGGTTAGGGTTAGGGGTT AGGGTTAGGGTAGGGTTAGGGTTAGGGGTTAGGGTTAGGGGTTAGGGGTTAGGGGTTAGGGTTAGGGTTA GGGGTAAGGGGTTAGGGTTAGGCGTTAGGGTTAGGGTTAGGGTTAGGGTTAGGGTTTGGGTTAGGGTTAG GGTTAGGGTTACAGTTAGGGTTAGGGTTAGAGTCAGTTAGGGTTAGGGTTAGGGTTTAGGGTTAGGGTTA GGGGTTAGGGTTAGGGTTAGGGTTAGGGTTAGGGTTAGGCTTGATTCCCACGTGATTCCCTCCTGATTCC CACGTGATTCCCACGTGATTCCCACGTGATTCCCACGTCACTCCCACGTGATTCCCACGTGATTCCCACG TGACTGAGACGTGATTCCCACGTGATTCCCACGTGATTCCCACGCGATTTCCACATGATTCCCACGTGAT
http://www.ncbi.nlm.nih.gov/nuccore/DP000828
GCTGCATATAGGCCCAGAGTTCTGAGATGGTGGAATGAACCAACTGGACACTTAAAGAGACACTCCAAGT GGATTAGAGAGACTGACTGCTCTAGGGATTGGGCTAGGGCTCGGGCTTGGGCTCGGGTTTGGGGTTCGGG TTCGGGGTTCGGGTTCAGGCTCGGGCTCGGGTTTGGGGTTCGGGTTCGGGTTAGGGTTCGAGTTAGGGTT CGGGTTCGGGTTCGGGTTAGGGTTCGGGTTCGGGTTCGGGTTCGGGTTAGGGTTAGGGTTCGGGTTCGGG TTAGGGGTTAGGGTTAGGGTTAGGGCTAGGGTTAGGGTTAGGGTTAGGGTTAGGGGTTAGGGTTAGGGTT AGGGTTAGGGGTTAGGGTTAGGGTTAGGGGTTAGGGTTAGGGGTTAGGGTTAGGGTTAGGGTTTAGGGTT AGGGTTAGGGTTAAGGTTAGGGTTAGGGGTTAGGGTTAGGGTTCGGGTTCGGGTTCGGGTTAGGGTTAGG GTTAGGGTTAGGGTTAGTGTTAGGGTTAGGGTTAGGTTTAGGGTTAGTGTTAGGGTTTAGGGTTAGGGTT AGGGTTAGGGTTAGGGGTTAGGGTTAGGGTTAGGGTTAGGGTTAGGCTTAGGGATTAGGGTTAGGGTTAG GGTTAGGGTTAGGGTTAGGGTTAGGGTTAGGGGTTAGGGTTAGGGTTAGCGTTTAGGTTTAGGATTAGGT TTAGGGTTAAGGTTAGGGTTAGGGTTTGGGTTAGGGTTAGCTCCCAGACGTACAGCTGCGAGAAGCCTCC TCTTGTGGTGCTTGTGGACAGTTGGCATTCCTCTTGATTTGAAGCTAGGAAATCAGCCCTCACCTCGAGA TGATTGGCGGAACACGGAGCTCTTTCTGCTTGCTGCAGTGACCTCAGTTTCCATCTTGACTTGAGACAGT
http://www.ncbi.nlm.nih.gov/nuccore/DP000829
CCGTGTAAACACACAGCCTTCCTAGGCCTTATGCCTCCTCGTCCATAAGGGGATGGTGGTTTTTCTGCTC ATGGGGTGGGGGGAGGGCACACCTATGGCCACAGCACTGGCTCCATGGACAGCATGGTTCCTTGGGGGCC TGGAGCCCCACAACTGATAAGACTGACACAAGAGCTGACATTAGGGTTCGGGTTCGGGTCAGGGTTCGGG TCAGGGTTCGGGTCAGGGGTTAGGGTCAGGGTTAGGGTCAGGGGTTAGGGTCAGGGTTAGGGTTAGGGTT AGGGGTTAGGGTCAGGGTCAGGGTCAGGGTCAGGGTCAGGGGTTAGGGTCAGGGTCAGGGTCAGGGTCAG GGTCAGGGTTAGGGGTTAGGGTTAGGGTTATGGTTTAGGGTTAGGGTTAGGGTTAGGGTTAGGGGTTAGG GTTAGGGTTAGGGTTTAGGGTTAGGGGTTAGGGTTAGGGTTAGGGTTAGGGTTTAGGGTTAGGGTTTAGG GTTAGGGTTAGGGTTAGGGTTTAGGGTTAGAGTTAAGGTTAGGGTTAGGGTTAGGGGTTAGGGTCAGGGT CAGGGTCAGGGGTTAGGGTCAGGGTCAGGGTCAGGGTCAGGTTAGGGTTAGGGTTAGGGTTAGGGTTTAG GGTTAGGGTTAGGGTTAGGGTTTAGGGTTAGGGTTTAGGGTTAGGATAAGGGTTAGGGTTTAGGGTTAGG GTTAGGGTTAGGGTTTAGGGTTTAGGGTTTAGGGTTAGGGTTAGGGTTAGGTTTAGTGTTTAGGGTTAGG GTTAGGGTTAGGTTTAGGTTAGGGTTAGGGTTAGGGTTTGGGTTAGGGTTAGGGTTAGGGTTAGGGGTTA GGGTTAGGGTTAGGCTTTAGGGTTAGGGTTAGGGTTTAGGATTAGGGTTAGGGTTAGGGTTAGGGTTAGG GTTAGGGTTTAGGGTTAGGGTTAGGGTTACGGTATAGGGTTAGGGTTAGGGTTAGGGTTAGGGTTTAGGG TTAGGTTTAGGGTTTGGGTTAGGGTTAGGGTTAGGGTGGAGGCCGCAAATTCAACCTCCCTCAACCAGAC CTACAGCTGCGAGAAGCCTCCTCTTGTGGTGCTTGTGGACAGTTGGCATTCCTCTTGATTTGAAGCCAGG AAATCAGCTCTCACCTCGAGATGATTCGGAATACACGGAGCTGTTTCTGGTTGGTGAAGTGACTTTAGGA
http://www.ncbi.nlm.nih.gov/nuccore/DP000830
CGTAGGAATGTGCCCATGAGATGAAAATATTGTCCTGAGTTGAAACGGAAGTTAAATTCAAAATCACGTT GATGAGGCCAAGCAGCAGGAGTTGATTATGTGACTTCATCCTGAAGGGGCTCATCCGGGATCTTCTTTTC CTTCTTCTTCCTGAGGATGATCTTAGTCTCTTGGGGGTCAGTGGAGTCCCTCTCTGCAGCCTGTTAGGGT TAGTGTTAGGGTTAGGGTTAGGGTTTAGGGATAGAGTTAGGGTTAGGGTTAGGGTTAGGGTTAGTTAGGG TTAGGGTTAGGGTTAGGATTAGGGTTTAGGGTAAGGGTTAGGGTTAGGGTTAGGGTTAGGGTTAGGGTTT AGGGTTAGGGTTAGGGTTAGTAATGGATGGGAGGCCGCCTGTCGAGAAAGGGCAGGGAGCTAGGGCTTTC TCTAGTGTCTCCGCAGGGGCTTCAGACATCCCTTCATCTTGTGAGATGAAATCCAGCTTGCACTCAGGTC ACTGCAGGAATTCCGGCCTGATTTCGTGTCAGGGCATCTCGGGATCGATTCCACTGGAGCTCGCAAATTC
In the Immortal Words of Dr Tomkins
First, the sequence was only about 800 bases long—not the 10,000 bases or more you would expect if two 5,000-base (or larger) telomeres fused together.
Second, the fusion-like sequence was very degenerate and only 70% similar to what one would expect of a pristine fusion sequence of the same size.
Who here agrees with him?
roohif 