Bat Beta2c Coronavirus Recombination Signals MERS Evolution
September 10, 2013
A recently released bat beta coronavirus sequence (203 BP – Taper/CII_KSA_287/Bisha/Saudi Arabia/2012 – Taphozous perforatus) from Bisha exactly matched the human case from Bisha, EMC/12. The bat sequence was more closely related to the human sequence than other human sequence strongly supporting a recent role of bats in the emergence of MERS in the Middle East. Prior to the Bisha bat sequence, the closest bat sequence was from a sample from South Africa, PML/2011/Neozul/RSA/2012 (from Neoromicia cf. zuluensis).
The initial South African sequence has been expanded (to 816 BP – positions 14817- 15637), and now covers the same 203 BP region represented by the Bisha bat. The South Africa sequence has 12 differences (94.1% identity) with the human consensus sequence, in contrast to the Bisha bat which has one difference, which is the same as the human sequence from Bisha. For the 816 BP region there are 53 difference with the human consensus (93.5% identity) confirming that the South African sequence did not play a recent role in the emergence of MERS-CoV.
However, the South African bat sequence had regions of strong identity with the human consensus (1 difference in positions 14998-15069 or 98.6% identity and 2 differences between positions 15119-15243 or 98.4% identity) highlighting a role for the South African bat sequence in the evolution of the human sequences (via homologous recombination).
The South African bat species, Neoromicia cf. zuluensis, has a large geographic reach in Africa, which extends into Ethiopia where it overlaps the geographic reach of Taphozous perforatus, suggesting bats harbor a wide variety of beta2c coronavirus sequences which evolve via recombination.