Engineering and Technology Journal

During the last decade, tilapia species (Cichlidae: Teleostei) became
members of Iraqi fish fauna. They characterized with morphological similarity among
genera and species. That makes species differentiation not easily. Molecular methods
followed to differentiate between redbelly tilapia Coptodon zillii (Gervais, 1848) and
blue tilapia Oreochromis aureus (Steindachner, 1864) of the Euphrates River sector
at Al-Samawah city. RAPD-PCR method used to create the genetic fingerprints of two
tilapia fish species. Seven decamer primers (OPA08, OPA10, OPA13, OPA17,
OPA19, OPB08 and OPC02) used to amplify DNA fragments using PCR-RAPD
technique. Forty-four bands scored after electrophoresis on 2% agarose gel along
with molecular marker fragmented to each 100 base pair. The molecular weight of
bands was calculated using PhotoCapt-MW software. The volume of bands ranged
from C. zillii 168 bp to 2227 bp while they ranged from 62 bp to 2154 bp in O.
aureus. The results achieve the RAPD fingerprints of two tilapia species in Euphrates
River at for genetic Al-Samawa city and draw the genetic tree with the same species
from Shatt A-Arab River in Basrah city. The study concluded that there is the closest
relatedness among tilapia populations from Euphrates and Shatt Al-Arab Rivers. The
results proved that RAPD markers were efficient to generate DNA fingerprints of
tilapia fish species. Furthermore, the utilizing of the RAPD markers can differentiate
the two studied species. The present study may be the first genetic study on these
tilapia fish species. Moreover, this would be the baseline studies in the future. In
addition, this study would be valuable for conservation program and documentation
of identities of tilapia fish species in Iraqi inland waters