A new molecular nomenclature for Taenia hydatigena: mitochondrial DNA sequences reveal sufficient diversity suggesting the assignment of major haplotype divisions

Abstract

Cysticercosis caused by the metacestode larval stage of Taenia hydatigena formerly referred to as Cysticercus tenuicollis is a disease of veterinary importance that constitutes a significant threat to livestock production worldwide, especially in endemic regions due to condemnation of visceral organs and mortality rate of infected young animals. While the genetic diversity among parasites is found to be potentially useful in many areas of research including molecular diagnostics, epidemiology and control, that of T. hydatigena across the globe remains poorly understood. In this study, analysis of the mitochondrial DNA (mtDNA) of adult worms and larval stages of T. hydatigena isolated from dogs, sheep and a wild boar in China showed that the population structure consists of two major haplogroups with very high nucleotide substitutions involving synonymous and non-synonymous changes. Compared with other cestodes such as Echinococcus spp., the genetic variation observed between the haplogroups is sufficient for the assignment of major haplotype or genotype division as both groups showed a total of 166 point-mutation differences between the 12 mitochondrial protein-coding gene sequences. Preliminary analysis of a nuclear protein-coding gene (pepck) did not reveal any peculiar changes between both groups which suggests that these variants may only differ in their mitochondrial makeup.

Prevalence and phylogeography of Taenia hydatigena metacestodes from goats of India

“…The consumption of meat infected with C. tenuicollis does not cause any harm to human beings, however it remains a threat to livestock production (Ohiolei et al ., 2021). The genetic diversity of T. hydatigena / C. tenuicollis within populations is poorly understood due to limited studies (Ohiolei et al ., 2021).…”

“…The consumption of meat infected with C. tenuicollis does not cause any harm to human beings, however it remains a threat to livestock production (Ohiolei et al ., 2021). The genetic diversity of T. hydatigena / C. tenuicollis within populations is poorly understood due to limited studies (Ohiolei et al ., 2021). A proper understanding of the genetic diversity is required for epidemiological investigation, anthelmintic treatment, vaccine/drug development and control (Ohiolei et al ., 2021).…”

“…The genetic diversity of T. hydatigena / C. tenuicollis within populations is poorly understood due to limited studies (Ohiolei et al ., 2021). A proper understanding of the genetic diversity is required for epidemiological investigation, anthelmintic treatment, vaccine/drug development and control (Ohiolei et al ., 2021). Recent studies had reported a high variation between T. hydatigena populations, establishing its 2 haplogroups (Ohiolei et al ., 2019, 2021).…”

“…A proper understanding of the genetic diversity is required for epidemiological investigation, anthelmintic treatment, vaccine/drug development and control (Ohiolei et al ., 2021). Recent studies had reported a high variation between T. hydatigena populations, establishing its 2 haplogroups (Ohiolei et al ., 2019, 2021). However, in the present study, we had observed a low genetic diversity of T. hydatigena across north India.…”

“…Globally, a few reports targeting mitochondrial gene sequences (partial cox 1 and nad 1) had reported considerable levels of genetic diversity among T. hydatigena populations from different hosts and geographical regions (Kedra et al ., 2001; Boufana et al ., 2015; Braae et al ., 2015; Rostami et al ., 2015; Omar et al ., 2016; Adwan et al ., 2018; Ohiolei et al ., 2019; Sarvi et al ., 2020; Ohiolei et al ., 2021).…”