Genetic structure and relationships within and between cultivated and wild sorghum (Sorghum bicolor (L.) Moench) in Kenya as revealed by microsatellite markers.

Understanding the extent and partitioning of diversity within and among crop landraces and their wild/weedy relatives constitutes the first step in conserving and unlocking their genetic potential. This study aimed to characterize the genetic structure and relationships within and between cultivated and wild sorghum at country scale in Kenya, and to elucidate some of the underlying evolutionary mechanisms. We analyzed at total of 439 individuals comprising 329 cultivated and 110 wild sorghums using 24 microsatellite markers. We observed a total of 295 alleles across all loci and individuals, with 257 different alleles being detected in the cultivated sorghum gene pool and 238 alleles in the wild sorghum gene pool. We found that the wild sorghum gene pool harbored significantly more genetic diversity than its domesticated counterpart, a reflection that domestication of sorghum was accompanied by a genetic bottleneck. Overall, our study found close genetic proximity between cultivated sorghum and its wild progenitor, with the extent of crop-wild divergence varying among cultivation regions. The observed genetic proximity may have arisen primarily due to historical and/or contemporary gene flow between the two congeners, with differences in farmers' practices explaining inter-regional gene flow differences. This suggests that deployment of transgenic sorghum in Kenya may lead to escape of transgenes into wild-weedy sorghum relatives. In both cultivated and wild sorghum, genetic diversity was found to be structured more along geographical level than agro-climatic level. This indicated that gene flow and genetic drift contributed to shaping the contemporary genetic structure in the two congeners. Spatial autocorrelation analysis revealed a strong spatial genetic structure in both cultivated and wild sorghums at the country scale, which could be explained by medium- to long-distance seed movement.

Community-based screening for pre-hypertension among military active duty personnel.

OBJECTIVE: To determine the prevalence of both pre-hypertension and hypertension, and risk factors associated with the newly diagnosed Saudi military active duty personnel. METHODS: A community-based cross-sectional screening of 1238 Saudi military active duty service personnel was conducted during the period from September to December 2007 at the military units of Taif region, western Saudi Arabia. Screening tools included self-administrated questionnaire, general physical examination, anthropometric measurements, and assessment of blood pressure. RESULTS: All participants were Saudi males. Their age ranged from +/-7.02. By applying the Joint National Committee on prevention, detection, evaluation, and treatment of high hypertension criteria, 214 (17.3%) were considered pre-hypertensive. Multivariate logistic regression analysis showed that obesity as measured by body mass index [odds ratio (OR)=2.71, confidence interval (CI): 1.39-5.28], positive family history (OR=1.46, CI: 1.03-2.06), ever smoking (OR=1.45, CI: 1.05-2.02), and increased waist circumference (OR=1.04, CI: 1.02-1.06) were the significant predictors of hypertension among military active duty personnel. CONCLUSION: Pre-hypertension is a common hidden problem and it predicts the development of frank hypertension. Findings of the current study support the recommendation of lifestyle modification for pre-hypertension patients. However, further prospective studies are required to determine the role of pharmacotherapy in pre-hypertension.