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Effective Tuberculosis (TB) control measures in Oman have reduced the annual incidence of tuberculosis cases by 92% between 1981 and 2016. However, the current incidence remains above the program control target oflt;1 TB case per 100,000 population. This has been partly attributed to a high influx of migrants from countries with high TB burdens. The present study aimed to elucidate

Spinocerebellar ataxia with axonal neuropathy type 1 (SCAN1; OMIM # 607250 ), an exceedingly rare disorder having been documented in only a single family from Saudi Arabia, is the result of an unusual mutation in the tyrosyl DNA phosphodiesterase 1 gene (TDP1). We performed high-throughput sequencing (whole exome and ataxia gene panel) in two apparently unrelated Omani families segregating sensorimotor neuropathy and ataxia in an autosomal recessive fashion. Following validation by Sanger sequencing, all affected subjects (n = 4) were confirmed to carry the known SCAN1 pathogenic homozygous variant in the TDP1 gene, NM_001008744.1:c.1478A > G (p.His493Arg). In keeping with the initial description, our patients demonstrated progressive ataxia, cerebellar atrophy and disabling axonal sensori-motor neuropathy (n = 4), hypercholesterolemia (n = 2) and elevated serum alpha fetoprotein (n = 3). In addition, our patients also had mild cognitive deficits in multiple domains (n = 3), a feature not previously reported. Our findings independently revalidate the phenotype of TDP1 mutation and expand the clinical spectrum to include mild cognitive deficits. Haplotype sharing, as determined by DNA microarray (CytoScan HD), attests to a possible common founder mutation in the Arab population.

Background: Theileriosis is one of the most prevalent infectious diseases of livestock in the Arabian Peninsula,\ud and causes high rates of mortality and morbidity in sheep and cattle. However, there is a paucity of information\ud on the distribution of Theileria spp. over the whole region and their impact on different hosts. The present study\ud carried out a country-wide molecular survey for Theileria spp. of livestock in Oman across four governorates. The\ud aim of the survey was to define the prevalence of Theileria spp. in cattle, sheep and goats, highlight risk factors\ud for infection and identify the main tick species involved in parasite transmission.\ud Material and methods: A total of 2020 animals were examined in the survey consisting of sheep [n = 592], goats\ud [n = 981] and cattle [n = 447]. All three species were raised and co-grazed on the same farms. Theileria\ud parasites were detected using PCR-RFLP and RLB of the 18S rRNA gene. Cloning and sequencing of the 18S rRNA\ud was carried out on 11 T. lestoquardi isolates from Ash-Sharqiyah, and Ad-Dhahira governorates, and phylogenetic\ud relationships were inferred using additional sequences of T. lestoquardi, T. annulata and T. ovis available in\ud GenBank.\ud Results: Theileria spp. prevalence was 72.3%, 36.7% and 2.7% among cattle, sheep and goats, respectively.\ud Strong similarity in results was obtained using RLB and PCR-RFLP for detection of Theileria spp. however, RLB\ud detected a higher rate of mixed infection than PCR-RFPL (P < 0.001). Theileria annulata was the only parasite\ud detected in cattle, while sheep and goats carried T. ovis, T. lestoquardi and T. annulata as well as Theileria spp.\ud OT1. Of the four Theileria spp. detected in small ruminants, overall T. ovis was most prevalent (sheep [33.4%],\ud goats [2.0%]), whereas T. lestoquardi was less prevalent (sheep [22.0%], goats [0.5%]). A large proportion of\ud infected sheep (19%) carried mixed infection of T. ovis and T. lestoquardi. However, single T. lestoquardi\ud infections (3.0%) were less prevalent than T. ovis infections (14.5%). Risk of Theileria spp. infection was\ud significantly higher for exotic breeds, relative to native breeds, of cattle (p = 0.00002) and sheep (p = 0.005).\ud Phylogenetic analysis placed T. lestoquardi in Oman in the same clade as other T. lestoquardi strains isolated from\ud the same regional area (Iraq and Iran). The main tick species, identified on the examined animals, Hyalomma\ud anatolicum, was widely distributed and was found in all of the surveyed governorates.\ud Conclusion: Theileria spp. are widespread in Oman with variable prevalence detected in different regions. Two\ud economically important hosts, cattle and sheep are at high risk from virulent T. annulata and T. lestoquardi,\ud respectively. The survey indicates extensive exposure to ticks and transmission of infection that has a significant\ud economic impact. The higher prevalence of T. lestoquardi as mixed rather than single infection requires further\ud investigation.

BackgroundTheileriosis, caused by a number of species within the genus Theileria, is a common disease of livestock in Oman. It is a major constraint to the development of the livestock industry due to a high rate of morbidity and mortality in both cattle and sheep. Since little is currently known about the genetic diversity of the parasites causing theileriosis in Oman, the present study was designed to address this issue with specific regard to T. annulata in cattle.MethodsBlood samples were collected from cattle from four geographically distinct regions in Oman for genetic analysis of the Theileria annulata population. Ten genetic markers (micro- and mini-satellites) representing all four chromosomes of T. annulata were applied to these samples using a combination of PCR amplification and fragment analysis. The resultant genetic data was analysed to provide a first insight into the structure of the T. annulata population in Oman.ResultsWe applied ten micro- and mini-satellite markers to a total of 310 samples obtained from different regions (174 [56%] from Dhofar, 68 [22%] from Dhira, 44 [14.5%] from Batinah and 24 [8%] from Sharqia). A high degree of allelic diversity was observed among the four parasite populations. Expected heterozygosity for each site ranged from 0.816 to 0.854. A high multiplicity of infection was observed in individual hosts, with an average of 3.3 to 3.4 alleles per locus, in samples derived from Batinah, Dhofar and Sharqia regions. In samples from Dhira region, an average of 2.9 alleles per locus was observed. Mild but statistically significant linkage disequilibrium between pairs of markers was observed in populations from three of the four regions. In contrast, when the analysis was performed at farm level, no significant linkage disequilibrium was observed. Finally, no significant genetic differentiation was seen between the four populations, with most pair-wise FST values being less than 0.03. Slightly higher FST values (GST’ = 0.075, θ = 0.07) were detected when the data for T. annulata parasites in Oman was compared with that previously generated for Turkey and Tunisia.ConclusionGenetic analyses of T. annulata samples representing four geographical regions in Oman revealed a high level of genetic diversity in the parasite population. There was little evidence of genetic differentiation between parasites from different regions, and a high level of genetic diversity was maintained within each sub-population. These findings are consistent with a high parasite transmission rate and frequent movement of animals between different regions in Oman.