Universal primers for amplification of mitochondrial small subunit ribosomal RNA-encoding gene in scleractinian corals

We describe the construction of polymerase chain reaction primers designed to amplify a portion of the mitochondrial (mt) small subunit ribosomal (SSU ) RNA-encoding genes in scleractinian corals. Combinations of cloning and s equencing show that the amplified fragments are between 694 and 896 bp in l ength. Alignment of the amplified DNA sequences to the published mt SSU rRN A genes of Metridium senile and Sarcophyton glaucum indicates several conse rved regions among actiniarian, corallimorpharian, octocorallian, and scler actinians, suggesting this primer set can successfully amplify over 80% or the mt SSU rDNA region of scleractinian corals. Surveys of sequence variati on and estimation of the rate of evolution show an extremely slow divergenc e of the SSU rRNA gene in the family Acroporidae.