Quantitative trait locus mapping and functional genomics of an organophosphate resistance trait in the western corn rootworm, Diabrotica virgifera virgifera.

The western corn rootworm, Diabrotica virgifera virgifera, is an insect pest of corn and population suppression with chemical insecticides is an important management tool. Traits conferring organophosphate insecticide resistance have increased in frequency amongst D. v. virgifera populations, resulting in the reduced efficacy in many corn-growing regions of the USA. We used comparative functional genomic and quantitative trait locus (QTL) mapping approaches to investigate the genetic basis of D. v. virgifera resistance to the organophosphate methyl-parathion. RNA from adult methyl-parathion resistant and susceptible adults was hybridized to 8331 microarray probes. The results predicted that 11 transcripts were significantly up-regulated in resistant phenotypes, with the most significant (fold increases ≥ 2.43) being an α-esterase-like transcript. Differential expression was validated only for the α-esterase (ST020027A20C03), with 11- to 13-fold greater expression in methyl-parathion resistant adults (P < 0.05). Progeny with a segregating methyl-parathion resistance trait were obtained from a reciprocal backcross design. QTL analyses of high-throughput single nucleotide polymorphism genotype data predicted involvement of a single genome interval. These data suggest that a specific carboyxesterase may function in field-evolved corn rootworm resistance to organophosphates, even though direct linkage between the QTL and this locus could not be established.

Health-related quality of life of diabetic Pima Indians.

This study was designed to measure the health-related quality of life of a sample of diabetic Pima Indians. Health status questionnaires were administered to 54 diabetic Pima Indians attending an outpatient pharmacy in southern Arizona. Health-related quality of life was assessed using the SF-36 Health Survey. Internal consistencies of the eight multi-item scales of the SF-36 were estimated. Nonparametric analyses were performed to determine relationships between mean SF-36 scale scores and various clinical and demographic variables. Favorable internal consistencies for the multi-item scales were observed, with alpha coefficients ranging from 0.63 to 0.91. SF-36 scale scores were not influenced by sex or education level. Age was significantly associated with four of the eight dimensions. Indicators of glycemic control were not significantly associated with any SF-36 multi-item scale scores. Subjects with more comorbid chronic conditions had significantly lower SF-36 scores. If the goal of maximizing health status of American Indians is to be reached, health-related quality-of-life assessment should be used as a means to monitor progress toward that goal. Further evaluation of the SF-36 or other health status/quality-of-life instruments in this population should be undertaken.