Phylogenetic analysis of kinetoplast DNA: kDNA of Leishmania tropica in Thi-Qar province, Iraq.

• Thi-Qar province considers one of the mixed foci of cutaneous and visceral leishmaniasis, which is considered as widely health problem and is an uncontrolled disease. • The phylogenetic relationship and sequncing analysis of L. tropica isolates have not been studied before in the local area. • The nested PCR assay is considered a suitable method for identifying Leishmania parasites in clinical samples. The Kinetoplast DNA minicircle gene has showed high sensitivity and specificity to characterize the parasite. • The kDNA minicircle sequences analysis results have showed variation of the local isolates that decrease whenever approached from the Iranian border. This means that L.tropica may transmit from Iran. Cutaneous leishmaniasis (CL) is one of wobbling endemic disease in Iraq, that cause intracellular obligate protistan parasite returned to the genus Leishmania. This study is aimed to identify epidemiology of CL, detect the prevalence of Leishmania tropica and find the phylogenetic relationship. The current study was conducted in the main hospitals of Thi-Qar province-south of Iraq for period from November 2018 to October 2019. Nested-PCR was used to amplify kinetoplast minicircle fragments DNA. It was recorded 247 clinical cases with CL, the infections of males were higher than females, while infection rate appeared gradual reduction with age progress. Furthermore, the most CL infections were as single lesions and occurred in December. The infections of upper limbs were high when compared with other body regions. The molecular diagnosis showed L. tropica was more frequently. DNA sequences of kDNA gene of L. tropica showed confirmative genetic detection of local isolates using NCBI-Blast data and phylogenetic tree analysis after comparison with global recorded isolates. The local L. tropica isolates showed genetically closed related to NCBI-Blast L. tropica with accession number AB678350.1. Generally, the analysis of kDNA nitrogen bases sequences showed that all of samples were consistent with those recorded at the NCBI. The kDNA minicircle sequences analysis results showed mismatching of the local isolates decrease whenever approached from the Iranian border. In addition, genetic heterogeneity diagnosis is important for detection of therapy, control and epidemiological studies. [ABSTRACT FROM AUTHOR]